Experimental study of inequality and unpredictability in an artificial cultural market.
Salganik, Matthew J; Dodds, Peter Sheridan; Watts, Duncan J
2006-02-10
Hit songs, books, and movies are many times more successful than average, suggesting that "the best" alternatives are qualitatively different from "the rest"; yet experts routinely fail to predict which products will succeed. We investigated this paradox experimentally, by creating an artificial "music market" in which 14,341 participants downloaded previously unknown songs either with or without knowledge of previous participants' choices. Increasing the strength of social influence increased both inequality and unpredictability of success. Success was also only partly determined by quality: The best songs rarely did poorly, and the worst rarely did well, but any other result was possible.
Karimov, Jamshid H; Sunagawa, Gengo; Such, Kimberly A; Sale, Shiva; Golding, Leonard A R; Moazami, Nader; Fukamachi, Kiyotaka
2015-12-01
The biocompatibility assessment of the Cleveland Clinic continuous-flow total artificial heart is an important part of the device developmental program. Surgical and postoperative management are key factors in achieving optimal outcomes. However, the presence of vascular anatomical abnormalities in experimental animal models is often unpredictable and may worsen the expected outcomes. We report a technical impediment encountered during total artificial heart implantation complicated by unfavorable bovine anatomy of the ascending aorta and brachiocephalic arterial trunk.
NASA Astrophysics Data System (ADS)
Dick, S. J.
2009-12-01
The Drake Equation for the number of radio communicative technological civilizations in the Galaxy encompasses three components of cosmic evolution: astronomical, biological and cultural. Of these three, cultural evolution totally dominates in terms of the rapidity of its effects. Yet, SETI scientists do not take cultural evolution into account, perhaps for understandable reasons, since cultural evolution is not well-understood even on Earth and is unpredictable in its outcome. But the one certainty for technical civilizations billions, millions, or even thousands of years older than ours is that they will have undergone cultural evolution. Cultural evolution potentially takes place in many directions, but this paper argues that its central driving force is the maintenance, improvement and perpetuation of knowledge and intelligence, and that to the extent intelligence can be improved, it will be improved. Applying this principle to life in the universe, extraterrestrials will have sought the best way to improve their intelligence. One possibility is that they may have long ago advanced beyond flesh-and-blood to artificial intelligence, constituting a postbiological universe. Although this subject has been broached, it has not been given the attention it is due from its foundation in cultural evolution. Nor has the idea of a postbiological universe been carried to its logical conclusion, including a careful analysis of the implications for SETI. SETI scientists, social scientists, and experts in AI should consider the strengths and weaknesses of this new paradigm.
The benefits of social influence in optimized cultural markets.
Abeliuk, Andrés; Berbeglia, Gerardo; Cebrian, Manuel; Van Hentenryck, Pascal
2015-01-01
Social influence has been shown to create significant unpredictability in cultural markets, providing one potential explanation why experts routinely fail at predicting commercial success of cultural products. As a result, social influence is often presented in a negative light. Here, we show the benefits of social influence for cultural markets. We present a policy that uses product quality, appeal, position bias and social influence to maximize expected profits in the market. Our computational experiments show that our profit-maximizing policy leverages social influence to produce significant performance benefits for the market, while our theoretical analysis proves that our policy outperforms in expectation any policy not displaying social signals. Our results contrast with earlier work which focused on showing the unpredictability and inequalities created by social influence. Not only do we show for the first time that, under our policy, dynamically showing consumers positive social signals increases the expected profit of the seller in cultural markets. We also show that, in reasonable settings, our profit-maximizing policy does not introduce significant unpredictability and identifies "blockbusters". Overall, these results shed new light on the nature of social influence and how it can be leveraged for the benefits of the market.
How to create a health care organization that can succeed in an unpredictable future.
Olden, Peter C; Haynos, Jessika
2013-01-01
For those who manage organizations, it has been said that success does not come from predicting the future but instead comes from creating an organization that can succeed in an unpredictable future. Managers are responsible for creating such an organization. To do that, managers can apply management-related principles and methods. This article explains selected principles of organization structure, human resources, culture, decision making, and change management and how to apply them to health care organizations. If done well, that will help such organizations succeed in an unpredictable future.
Active vision in satellite scene analysis
NASA Technical Reports Server (NTRS)
Naillon, Martine
1994-01-01
In earth observation or planetary exploration it is necessary to have more and, more autonomous systems, able to adapt to unpredictable situations. This imposes the use, in artificial systems, of new concepts in cognition, based on the fact that perception should not be separated from recognition and decision making levels. This means that low level signal processing (perception level) should interact with symbolic and high level processing (decision level). This paper is going to describe the new concept of active vision, implemented in Distributed Artificial Intelligence by Dassault Aviation following a 'structuralist' principle. An application to spatial image interpretation is given, oriented toward flexible robotics.
ERIC Educational Resources Information Center
Remer, Rory
2007-01-01
Cultural values, cross-cultural interaction patterns that are produced by dynamical (chaotic) systems, have a significant impact on interaction, particularly among and between people from different cultures. The butterfly effect, which states that small differences in initial conditions may have severe consequences for patterns in the long run,…
Developing Realistic Behaviors in Adversarial Agents for Air Combat Simulation
1993-12-01
34Building Symbolic Primitives with Continuous Control Rou- tines." Proceedings of the 1st International Conference on Aritificial Intelligence Planning...shortcoming is the minimal Air Force participation in this field. 1-1 Some of the artificial intelligence (AI) personnel at the Air Force Institute of... intelligent system that operates in a moderately complex or unpredictable environment must be reactive. In being reactive the intelligent system must
Development of programmable artificial neural networks
NASA Technical Reports Server (NTRS)
Meade, Andrew J.
1993-01-01
Conventionally programmed digital computers can process numbers with great speed and precision, but do not easily recognize patterns or imprecise or contradictory data. Instead of being programmed in the conventional sense, artificial neural networks are capable of self-learning through exposure to repeated examples. However, the training of an ANN can be a time consuming and unpredictable process. A general method is being developed to mate the adaptability of the ANN with the speed and precision of the digital computer. This method was successful in building feedforward networks that can approximate functions and their partial derivatives from examples in a single iteration. The general method also allows the formation of feedforward networks that can approximate the solution to nonlinear ordinary and partial differential equations to desired accuracy without the need of examples. It is believed that continued research will produce artificial neural networks that can be used with confidence in practical scientific computing and engineering applications.
Numerical solution of differential equations by artificial neural networks
NASA Technical Reports Server (NTRS)
Meade, Andrew J., Jr.
1995-01-01
Conventionally programmed digital computers can process numbers with great speed and precision, but do not easily recognize patterns or imprecise or contradictory data. Instead of being programmed in the conventional sense, artificial neural networks (ANN's) are capable of self-learning through exposure to repeated examples. However, the training of an ANN can be a time consuming and unpredictable process. A general method is being developed by the author to mate the adaptability of the ANN with the speed and precision of the digital computer. This method has been successful in building feedforward networks that can approximate functions and their partial derivatives from examples in a single iteration. The general method also allows the formation of feedforward networks that can approximate the solution to nonlinear ordinary and partial differential equations to desired accuracy without the need of examples. It is believed that continued research will produce artificial neural networks that can be used with confidence in practical scientific computing and engineering applications.
Petri, Aspasia; Karabetsos, Efthymios
2018-06-08
Herein, the strategic framework for the development and enhancement of safety culture in the artificial tanning sector in Greece is presented. This framework has been designed and promoted by the competent national regulatory authority, which is the Greek Atomic Energy Commission (EEAE). The aim is to ensure a common understanding regarding ultraviolet radiation (UVR) and artificial tanning among the artificial tanning professionals, the stakeholders and the general public. The strategic framework is founded on the international organizations' recommendations, the EU requirements and the relevant technical standards. It is comprised of three autonomous but interconnected components: A) A sunbed operators' e-training course and certification process, B) A code of practice addressed individually to the business owners, the sunbeds operators and the sunbeds users, C) Communication strategies aiming to raise awareness regarding UVR and artificial tanning to all the interested parties. The artificial tanning safety culture framework presented here is the policy option that EEAE undertook and it is embedded in the upcoming legislation and regulations for the provision of artificial tanning services in Greece. EEAE considers that the structure of the artificial tanning safety culture strategic framework will serve as the guide for the development and promotion of relevant safety culture strategic frameworks for the provision of aesthetic/wellness services that utilize other non-ionizing radiation sources, which currently don't exist. © 2018 IOP Publishing Ltd.
ERIC Educational Resources Information Center
Ilola, Lisa Marie
This study describes an intercultural learning program combining cooperative learning with critical incidents drawn from the culture-general assimilator developed by Brislin. The training program was adapted to school teachers, a population already identified as a high-risk group because of the frequency and unpredictability of the intercultural…
Cultural beliefs about a patient's right time to die: an exploratory study.
Perkins, Henry S; Cortez, Josie D; Hazuda, Helen P
2009-11-01
Generalist physicians must often counsel patients or their families about the right time to die, but feel ill-prepared to do so. Patient beliefs may help guide the discussions. Because little prior research addresses such beliefs, we investigated them in this exploratory, hypothesis-generating study. Anticipating culture as a key influence, we interviewed 26 Mexican Americans (MAs), 18 Euro-Americans (EAs), and 14 African Americans (AAs) and content-analyzed their responses. Nearly all subjects regardless of ethnic group or gender said God determines (at least partially) a patient's right time to die, and serious disease signals it. Yet subjects differed by ethnic group over other signals for that time. Patient suffering and dependence on "artificial" life support signaled it for the MAs; patient acceptance of death signaled it for the EAs; and patient suffering and family presence at or before the death signaled it for the AAs. Subjects also differed by gender over other beliefs. In all ethnic groups more men than women said the time of death is unpredictable; but more women than men said the time of death is preset, and family suffering signals it. Furthermore, most MA women--but few others--explicitly declared that family have an important say in determining a patient's right time to die. No confounding occurred by religion. Americans may share some beliefs about the right time to die but differ by ethnic group or gender over other beliefs about that time. Quality end-of-life care requires accommodating such differences whenever reasonable.
NASA Astrophysics Data System (ADS)
Lee, Sanghoon; Yoon, Heesung; Park, Byeong-Hak; Lee, Kang-Kun
2017-04-01
Groundwater use has been increased for various purposes like agriculture, industry or drinking water in recent years, the issue related to sustainability on the groundwater use also has been raised. Accordingly, forecasting the groundwater level is of great importance for planning sustainable use of groundwater. In a small island surrounded by the Han River, South Korea, seasonal fluctuation of the groundwater level is characterized by multiple factors such as recharge/discharge event of the Paldang dam, Water Curtain Cultivation (WCC) during the winter season, operation of Groundwater Heat Pump System (GWHP). For a period when the dam operation is only occurred in the study area, a prediction of the groundwater level can be easily achieved by a simple cross-correlation model. However, for a period when the WCC and the GWHP systems are working together, the groundwater level prediction is challenging due to its unpredictable operation of the two systems. This study performed Artificial Neural Network (ANN) model to forecast the groundwater level in the river area reflecting the various predictable/unpredictable factors. For constructing the ANN models, two monitoring wells, YSN1 and YSO8, which are located near the injection and abstraction wells for the GWHP system were selected, respectively. By training with the groundwater level data measured in January 2015 to August 2015, response of groundwater level by each of the surface water level, the WCC and the GWHP system were evaluated. Consequentially, groundwater levels in December 2015 to March 2016 were predicted by ANN models, providing optimal fits in comparison to the observed water levels. This study suggests that the ANN model is a useful tool to forecast the groundwater level in terms of the management of groundwater. Acknowledgement : Financial support was provided by the "R&D Project on Environmental Management of Geologic CO2 Storage" from the KEITI (Project Number: 2014001810003) This research was supported by "BK 21plus project of the Korean Government"
Liu, Yonggang; Tan, Peng; Liu, Shanshan; Shi, Hang; Feng, Xin; Ma, Qun
2015-01-01
Objective: Calculus bovis have been widely used in Chinese herbology for the treatment of hyperpyrexia, convulsions, and epilepsy. Nowadays, due to the limited source and high market price, the substitutes, artificial and in vitro cultured Calculus bovis, are getting more and more commonly used. The adulteration phenomenon is serious. Therefore, it is crucial to establish a fast and simple method in discriminating the natural, artificial and in vitro cultured Calculus bovis. Bile acids, one of the main active constituents, are taken as an important indicator for evaluating the quality of Calculus bovis and the substitutes. Several techniques have been built to analyze bile acids in Calculus bovis. Whereas, as bile acids are with poor ultraviolet absorbance and high structural similarity, effective technology for identification and quality control is still lacking. Methods: In this study, high-performance liquid chromatography (HPLC) coupled with tandem mass spectrometry (LC/MS/MS) was applied in the analysis of bile acids, which effectively identified natural, artificial and in vitro cultured Calculus bovis and provide a new method for their quality control. Results: Natural, artificial and in vitro cultured Calculus bovis were differentiated by bile acids analysis. A new compound with protonated molecule at m/z 405 was found, which we called 3α, 12α-dihydroxy-7-oxo-5α-cholanic acid. This compound was discovered in in vitro cultured Calculus bovis, but almost not detected in natural and artificial Calculus bovis. A total of 13 constituents was identified. Among them, three bio-markers, including glycocholic acid, glycodeoxycholic acid and taurocholic acid (TCA) were detected in both natural and artificial Calculus bovis, but the density of TCA was different in two kinds of Calculus bovis. In addition, the characteristics of bile acids were illustrated. Conclusions: The HPLC coupled with tandem MS (LC/MS/MS) method was feasible, easy, rapid and accurate in identifying natural, artificial and in vitro cultured Calculus bovis. PMID:25829769
The Emergent Power of Teacher Leaders
ERIC Educational Resources Information Center
Safir, Shane
2018-01-01
"Coming from complexity science, the term emergence describes the dynamic and unpredictable ways through which change unfolds in organizations," writes Shane Safir in this article about how teacher leaders can transform a school's climate and culture. Using Berkeley High School in California as an example, Safir explains how successful…
Mathematics, PISA, and Culture: An Unpredictable Relationship
ERIC Educational Resources Information Center
Andrews, Paul
2015-01-01
Recent studies have indicated, particularly in the European context, that students' mathematical successes on international tests of student achievement may not be attributable to the quality of classroom instruction, although, as is shown, this is unlikely to be the case in Flanders, the autonomous Dutch-speaking region of Belgium. Flemish…
ERIC Educational Resources Information Center
Popenoe, David
The increasing percentage of children living apart from their natural fathers is an unpredicted, and not widely discussed, trend. Fatherlessness is a major force behind many disturbing U.S. social problems. The institution of marriage acts as culture's chief vehicle to bind men to their children. The absence of fathers from children's lives is one…
Why the United States Must Adopt Lethal Autonomous Weapon Systems
2017-05-25
2017. http://www.designboom.com/ technology /designboom-tech-predictions-robotics-12-26- 2016/. Egan, Matt. "Robots Write Thousands Of News Stories A...views on the morality of artificial intelligence (AI) and robotics technology . Eastern culture sees artificial intelligence as an economic savior...Army, 37 pages. The East and West have differing views on the morality of artificial intelligence (AI) and robotics technology . Eastern culture
NASA Astrophysics Data System (ADS)
Radziszewski, Kacper
2017-10-01
The following paper presents the results of the research in the field of the machine learning, investigating the scope of application of the artificial neural networks algorithms as a tool in architectural design. The computational experiment was held using the backward propagation of errors method of training the artificial neural network, which was trained based on the geometry of the details of the Roman Corinthian order capital. During the experiment, as an input training data set, five local geometry parameters combined has given the best results: Theta, Pi, Rho in spherical coordinate system based on the capital volume centroid, followed by Z value of the Cartesian coordinate system and a distance from vertical planes created based on the capital symmetry. Additionally during the experiment, artificial neural network hidden layers optimal count and structure was found, giving results of the error below 0.2% for the mentioned before input parameters. Once successfully trained artificial network, was able to mimic the details composition on any other geometry type given. Despite of calculating the transformed geometry locally and separately for each of the thousands of surface points, system could create visually attractive and diverse, complex patterns. Designed tool, based on the supervised learning method of machine learning, gives possibility of generating new architectural forms- free of the designer’s imagination bounds. Implementing the infinitely broad computational methods of machine learning, or Artificial Intelligence in general, not only could accelerate and simplify the design process, but give an opportunity to explore never seen before, unpredictable forms or everyday architectural practice solutions.
Long-term culture of bovine nucleus pulposus explants in a native environment.
van Dijk, Bart G M; Potier, Esther; Ito, Keita
2013-04-01
Chronic low back pain is a disease with tremendous financial and social implications, and it is often caused by intervertebral disc degeneration. Regenerative therapies for disc repair are promising treatments, but they need to be tested in physiological models. To develop a physiological in vitro explant model that incorporates the native environment of the intervertebral disc, for example, hypoxia, low glucose, and high tissue osmolarity. Bovine nucleus pulposus (NP) explants were cultured for 42 days in conditions mimicking the native physiological environment. Two different approaches were used to balance the swelling pressure of the NP: raised medium osmolarity or an artificial annulus. Bovine NP explants were either cultured in media with osmolarity balanced at isotonic and hypertonic levels compared with the native tissue or cultured inside a fiber jacket used as an artificial annulus. Oxygen and glucose levels were set at either standard (21% O2 and 4.5 g/L glucose) or physiological (5% O2 and 1 g/L glucose) levels. Samples were analyzed at Day 0, 3, and 42 for tissue composition (water, sulfated glycosaminoglycans, DNA, and hydroxyproline contents and fixed charge density), tissue histology, cell viability, and cellular behavior with messenger RNA (mRNA) expression. Both the hypertonic culture and the artificial annulus approach maintained the tissue matrix composition for 42 days. At Day 3, mRNA expressions of aggrecan, collagen Type I, and collagen Type II in both hypertonic and artificial annulus cultures were not different from Day 0; however, at Day 42, the artificial annulus preserved the mRNA expression closer to Day 0. Gene expressions of matrix metalloprotease 13, tissue inhibitor of matrix metalloprotease 1, and tissue inhibitor of matrix metalloprotease 2 were downregulated under physiological O2 and glucose levels, whereas the other parameters analyzed were not affected. Although the hypertonic culture and the artificial annulus approach are both promising models to test regenerative therapies, the artificial annulus was better able to maintain a cellular behavior closer to the native tissue in longer term cultures. Copyright © 2013 Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Hammersley, Laura A.; Bilous, Rebecca H.; James, Sarah W.; Trau, Adam M.; Suchet-Pearson, Sandie
2014-01-01
Geographers are increasingly grappling with the theoretical and practical implications of integrating an ethics of reciprocity into undergraduate learning and teaching. This paper draws on the unexpected experiences of a third-year human geography research methods fieldtrip to examine the process of balancing undergraduate student learning and…
A Cross-Cultural Exploration of 'Wild' in Wilderness Therapy: Canada, Norway and Australia
ERIC Educational Resources Information Center
Harper, Nevin J.; Gabrielsen, Leiv E.; Carpenter, Cathryn
2018-01-01
This paper addresses pluralistic understandings of wilderness in the context of wilderness therapy (WT). The term wilderness perpetuates a modern worldview of place that beyond 'civilisation' exists an environment defined by risk, fear and an unpredictable nature. WT utilises outdoor travel and living practices during therapeutic intervention and…
Li, Yongcheng; Sun, Rong; Zhang, Bin; Wang, Yuechao; Li, Hongyi
2015-01-01
Neural networks are considered the origin of intelligence in organisms. In this paper, a new design of an intelligent system merging biological intelligence with artificial intelligence was created. It was based on a neural controller bidirectionally connected to an actual mobile robot to implement a novel vehicle. Two types of experimental preparations were utilized as the neural controller including 'random' and '4Q' (cultured neurons artificially divided into four interconnected parts) neural network. Compared to the random cultures, the '4Q' cultures presented absolutely different activities, and the robot controlled by the '4Q' network presented better capabilities in search tasks. Our results showed that neural cultures could be successfully employed to control an artificial agent; the robot performed better and better with the stimulus because of the short-term plasticity. A new framework is provided to investigate the bidirectional biological-artificial interface and develop new strategies for a future intelligent system using these simplified model systems.
Zhang, Bin; Wang, Yuechao; Li, Hongyi
2015-01-01
Neural networks are considered the origin of intelligence in organisms. In this paper, a new design of an intelligent system merging biological intelligence with artificial intelligence was created. It was based on a neural controller bidirectionally connected to an actual mobile robot to implement a novel vehicle. Two types of experimental preparations were utilized as the neural controller including ‘random’ and ‘4Q’ (cultured neurons artificially divided into four interconnected parts) neural network. Compared to the random cultures, the ‘4Q’ cultures presented absolutely different activities, and the robot controlled by the ‘4Q’ network presented better capabilities in search tasks. Our results showed that neural cultures could be successfully employed to control an artificial agent; the robot performed better and better with the stimulus because of the short-term plasticity. A new framework is provided to investigate the bidirectional biological-artificial interface and develop new strategies for a future intelligent system using these simplified model systems. PMID:25992579
Cultured High-Fidelity Three-Dimensional Human Urogenital Tract Carcinomas and Process
NASA Technical Reports Server (NTRS)
Goodwin, Thomas J. (Inventor); Prewett, Tacey L. (Inventor); Spaulding, Glenn F. (Inventor); Wolf, David A. (Inventor)
1998-01-01
Artificial high-fidelity three-dimensional human urogenital tract carcinomas are propagated under in vitro-microgravity conditions from carcinoma cells. Artificial high-fidelity three-dimensional human urogenital tract carcinomas are also propagated from a coculture of normal urogenital tract cells inoculated with carcinoma cells. The microgravity culture conditions may be microgravity or simulated microgravity created in a horizontal rotating wall culture vessel.
Derrida Meets IBM: Using Deconstruction To Teach Business Communication Students.
ERIC Educational Resources Information Center
Rice, H. William
The business communications teacher helps the student learn to write the proposal that wins a promotion or the sales letter that wins new customers. Students poised to enter the business world need language theories as much as students studying literature, for the corporate language culture is as unpredictable and ambiguous as any literary text.…
The Vertical Dynamics of Larval Chironomids on Artificial Substrates in Lake Lido (Bogor, Indonesia)
Wardiatno, Yusli; Krisanti, Majariana
2013-01-01
The composition and abundance of chironomid larval communities was studied on artificial substrates in Lido Lake, located in Bogor, West Java, Indonesia. The lake is organically enriched as a result of fish farming activity. Seventy two artificial substrates were deployed at three depths (2.0, 3.5 and 5.0 m) at two sites: a cage culture site and a non-cage culture site (control). Larval chironomid larvae were collected 7, 14, 28 and 56 days after the artificial substrates were deployed. In addition, selected physical and chemical parameters of the water were simultaneously measured. Three chironomid subfamilies, the Chironominae, Tanypodinae and Orthocladiinae, were found at both sites. At the cage culture site, both diversity and total abundance were significantly higher at the 2.0 and 3.5 m depths than at the 5.0 m depth, but this was not the case at the non-cage culture site. Based on pooling of the data from all depths, a Mann-Whitney U test showed that the non-cage culture site had a significantly higher diversity and total abundance than the cage culture site. Dissolved oxygen (DO) and turbidity showed significant differences between the 2.0 m depth and the 2 greater depths at the cage culture site, whereas none of the environmental parameters showed significant differences among the three depths at the non-cage culture site. A comparison of the environmental parameters at the same depth at the two sites showed significant differences in turbidity, pH and DO. A Spearman rank correlation analysis at the cage culture site showed that abundance and DO were positively correlated, whereas abundance and turbidity were negatively correlated. However, only pH was negatively correlated with abundance at the non-cage culture site. PMID:24575246
Phylogeny and active ingredients of artificial Ophiocordyceps lanpingensis ascomata
NASA Astrophysics Data System (ADS)
Chen, Zihong; Xu, Ling; Yu, Hong; Zeng, Wenbo; Dai, Yongdong; Wang, Yuanbing
2018-04-01
To evaluate the morphological character, phylogenesis and functional components of artificial Ophiocordyceps lanpingensis, a related species of O. sinensis. The ascomata of O. lanpingensis was induced with its asexual strain, HLANY0707 and its microscopic feature was described. Phylogenesis was analyzed with ITS-5.8S sequences of HLANY0707, its cultured stroma, and 39 relative sequences of Hirsutella and Ophiocordyceps based on the maximum likelihood tree. Six nucleosides of artificial O. lanpingensis, natural O. lanpingensis and natural O. sinensis were compared with HPLC analysis. Artificial ascomata of O. lanpingensis could be massively produced with HLANY0707 and had similar microscopic features as the nature specimens. Phylogenetic analysis showed that both the artificial and natural O. lanpingensis had closer relationship with O. sinensis, O. xuefengensis, H. uncinata and O. robertsii, the species whose massively cultured ascomata being not reported. Nucleosides of artificial O. lanpingensis were very similar to natural O. sinensis, implying a promising application prospect of artificial O. lanpingensis as an alternative to O. sinensis. It showed a promising way to develop artificial O. lanpingensis and conserve the rare and endangered species, O. sinensis.
ERIC Educational Resources Information Center
Hui, Sammy King Fai; Cheung, Hoi Yan
2015-01-01
Technical and vocational education and training (TVET) is often seen to be constraining and focused on specific skill development for specific occupations. This goal is at odds with the demands of a knowledge economy that requires more general educational outcomes for an uncertain and unpredictable labour market. For this reason, Hui (2012) has…
Fibronectin-tethered graphene oxide as an artificial matrix for osteogenesis.
Subbiah, Ramesh; Du, Ping; Van, Se Young; Suhaeri, Muhammad; Hwang, Mintai P; Lee, Kangwon; Park, Kwideok
2014-10-20
An artificial matrix (Fn-Tigra), consisting of graphene oxide (GO) and fibronectin (Fn), is developed on pure titanium (Ti) substrates via an electrodropping technique assisted with a custom-made coaxial needle. The morphology and topography of the resulting artificial matrix is orderly aligned and composed of porous microcavities. In addition, Fn is homogenously distributed and firmly bound onto GO as determined via immunofluorescence and elemental mapping, respectively. The artificial matrix is moderately hydrophobic (63.7°), and exhibits an average roughness of 546 nm and a Young's modulus (E) of approximately 4.8 GPa. The biocompatibility, cellular behavior, and osteogenic potential of preosteoblasts on Fn-Tigra are compared to those of cells cultured on Ti and Ti-GO (Tigra). Cell proliferation and viability are significantly higher on Fn-Tigra and Tigra than that of cells grown on Ti. Focal adhesion molecule (vinculin) expression is highly activated at the central and peripheral area of preosteoblasts when cultured on Fn-Tigra. Furthermore, we demonstrate enhanced in vitro osteogenic differentiation of preosteoblasts cultured on Fn-Tigra over those cultured on bare Ti, as determined via Alizarin red and von Kossa staining, and the analysis of osteocalcin, type I collagen, alkaline phosphatase activity, and calcium contents. Finally, we investigate the biophysical and biomechanical properties of the cells using AFM. While the height and roughness of preosteoblasts increased with time, cell surface area decreased during in vitro osteogenesis over 2 weeks. In addition, the E of cells cultured on Tigra and Fn-Tigra increase in a statistically significant and time-dependent manner by 30%, while those cultured on bare Ti retain a relatively consistent E. In summary, we engineer a biocompatible artificial matrix (Fn-Tigra) capable of osteogenic induction and consequently demonstrate its potential in bone tissue engineering applications.
The Role of Culture in the Language Classroom.
ERIC Educational Resources Information Center
Dwyer, David; Folarin-Schleicher, Antonia; Moshi, Lioba
1999-01-01
Discusses the role of culture in second language instruction; Examines properties of culture, culture as a product of human activity, culture as a shared product, culture as an artificial product, cultural diversity, cultural relativism, cultural sensitivity, and stages of cultural awareness. Focuses on how to teach cultural knowledge, and the…
ERIC Educational Resources Information Center
Salganik, Matthew J.; Watts, Duncan J.
2008-01-01
Individuals influence each others' decisions about cultural products such as songs, books, and movies; but to what extent can the perception of success become a "self-fulfilling prophecy"? We have explored this question experimentally by artificially inverting the true popularity of songs in an online "music market," in which 12,207 participants…
[Microbiological testing of the artificial gingival margin in dentures].
Hermann, Péter; Klein, Ildikó; Barna, Zsuzsanna; Kaán, Miklós; Fejérdy, Pál
2004-06-01
In everyday practice dental laboratories try to reproduce the natural form of sulcus gingivae at the transitional area between artificial teeth and gingiva of removable dentures, even on esthetically less important areas. Aim of these investigations were to examine how artificial recreation of the sulcus gingivae influences plaque retention, and what is the microbiological relevance of these. Investigations were carried out on the vestibular side of removable dentures of 32 randomly selected patients treated at the Department of Prosthodontics at the Faculty of Dentistry, Semmelweis University. Microbiological samples were taken from each patient using the same method. Samples were taken from the left upper first molars' artificial gingival margin using sterile paper points. Paper points were then transported in Eppendorf-tubes, in 2 ml of physiological saline solution, and processed within a two-hour period of time. Series dilutions were made of the sample solutions, then surface-streaked on Subaraud and Gentamycin, blood-agar, eosin-methylene blue and Mitis Salivarius culture enriched with Bacitracin. Subaraud culture was induced under aerob conditions, at room temperature for two days, then the total amount of fungi quantified. After pure-culturing Candida albicans ID-culture was used for identification, and BioMerieux ATB automatic equipment to identify different Candida species. From pure cultures identification was carried out with Gram-staining, Neisser-staining, catalase, oxidase and also with other biochemical reactions. Blood-agar was used to determine total germ count, and normal commensal pharyngeal and oral bacteria. After collecting the microbiological samples, the conventional shape of the dental margin of gingiva was abolished on one side of the dentures and a smooth transition was created between denture teeth and the artificial gingiva in the molar and premolar region. During our investigations only blastomycetes were found. Besides most common Candida albicans, Candida glabrata, tropicallis, spherica and lambica were also identified. Our patients did not miss artificial sulcus gingivae, had no aesthetic complaints about smooth transition between artificial teeth and gingiva. Microbiological investigations of the samples and the comparative analysis showed, that on the smooth transitional areas compared to conventionally shaped sulci significantly less gram-negative, gram-positive bacteria and oral fungi were found, and there was no plaque formation.
Artificial Exo-Society Modeling: a New Tool for SETI Research
NASA Astrophysics Data System (ADS)
Gardner, James N.
2002-01-01
One of the newest fields of complexity research is artificial society modeling. Methodologically related to artificial life research, artificial society modeling utilizes agent-based computer simulation tools like SWARM and SUGARSCAPE developed by the Santa Fe Institute, Los Alamos National Laboratory and the Bookings Institution in an effort to introduce an unprecedented degree of rigor and quantitative sophistication into social science research. The broad aim of artificial society modeling is to begin the development of a more unified social science that embeds cultural evolutionary processes in a computational environment that simulates demographics, the transmission of culture, conflict, economics, disease, the emergence of groups and coadaptation with an environment in a bottom-up fashion. When an artificial society computer model is run, artificial societal patterns emerge from the interaction of autonomous software agents (the "inhabitants" of the artificial society). Artificial society modeling invites the interpretation of society as a distributed computational system and the interpretation of social dynamics as a specialized category of computation. Artificial society modeling techniques offer the potential of computational simulation of hypothetical alien societies in much the same way that artificial life modeling techniques offer the potential to model hypothetical exobiological phenomena. NASA recently announced its intention to begin exploring the possibility of including artificial life research within the broad portfolio of scientific fields comprised by the interdisciplinary astrobiology research endeavor. It may be appropriate for SETI researchers to likewise commence an exploration of the possible inclusion of artificial exo-society modeling within the SETI research endeavor. Artificial exo-society modeling might be particularly useful in a post-detection environment by (1) coherently organizing the set of data points derived from a detected ETI signal, (2) mapping trends in the data points over time (assuming receipt of an extended ETI signal), and (3) projecting such trends forward to derive alternative cultural evolutionary scenarios for the exo-society under analysis. The latter exercise might be particularly useful to compensate for the inevitable time lag between generation of an ETI signal and receipt of an ETI signal on Earth. For this reason, such an exercise might be a helpful adjunct to the decisional process contemplated by Paragraph 9 of the Declaration of Principles Concerning Activities Following the Detection of Extraterrestrial Intelligence.
Scale of Unpredictability Beliefs: Reliability and Validity.
Ross, Lisa Thomson; Short, Stephen D; Garofano, Marina
2016-11-16
Experiencing unpredictability in the environment has a variety of negative outcomes. However, these are difficult to ascertain due to the lack of a psychometrically sound measure of unpredictability beliefs. This article summarizes the development of the Scale of Unpredictability Beliefs (SUB), which assesses perceptions about unpredictability in one's life, in other people, and in the world. In Study I, college students (N = 305) responded to 68 potential items as well as other scales. Exploratory factor analysis yielded three internally consistent subscales (Self, People, and World; 16 items total). Higher SUB scores correlated with more childhood family unpredictability, greater likelihood of parental alcohol abuse, stronger causal uncertainty, and lower self-efficacy. In Study II, a confirmatory factor analysis supported the three-factor solution (N = 186 college students). SUB scores correlated with personality, childhood family unpredictability, and control beliefs. In most instances the SUB predicted family unpredictability and control beliefs beyond existing unpredictability measures. Study III confirmed the factor structure and replicated family unpredictability associations in an adult sample (N = 483). This article provides preliminary support for this new multi-dimensional, self-report assessment of unpredictability beliefs, and ideas for future research are discussed.
NASA Astrophysics Data System (ADS)
Li, Qingchen; Cao, Guangxi; Xu, Wei
2018-01-01
Based on a multifractal detrending moving average algorithm (MFDMA), this study uses the fractionally autoregressive integrated moving average process (ARFIMA) to demonstrate the effectiveness of MFDMA in the detection of auto-correlation at different sample lengths and to simulate some artificial time series with the same length as the actual sample interval. We analyze the effect of predictable and unpredictable meteorological disasters on the US and Chinese stock markets and the degree of long memory in different sectors. Furthermore, we conduct a preliminary investigation to determine whether the fluctuations of financial markets caused by meteorological disasters are derived from the normal evolution of the financial system itself or not. We also propose several reasonable recommendations.
,; ,; ,; ,; ,
2011-01-01
The impetus for developing this document is through implementing the Rocky Reach Pacific Lamprey Management Plan (PLMP), a component of the Rocky Reach Comprehensive Settlement Agreement, both of which are discussed more thoroughly in Section 1.2. The ultimate goal of the PLMP is to achieve No Net Impact (NNI) to Pacific lamprey of ongoing operations of the Rocky Reach Hydroelectric Project. Conducting artificial propagation of Pacific lamprey was considered by the state and federal fishery agencies and Tribes that are parties to the Settlement Agreement as a potential Protection, Mitigation, and Enhancement measure (PME) for achieving NNI during the term of the current Rocky Reach license. This document is intended to provide guidance as to the feas ibility of culturing Pacific lamprey, the associated facilities necessary for culture practices, and identifying uncertainties for monitoring culture efficacy and rationale for implementing Pacific lamprey artificial propagation
Gurunathan, Baskar; Sahadevan, Renganathan
2012-07-01
Optimization of culture conditions for L-asparaginase production by submerged fermentation of Aspergillus terreus MTCC 1782 was studied using a 3-level central composite design of response surface methodology and artificial neural network linked genetic algorithm. The artificial neural network linked genetic algorithm was found to be more efficient than response surface methodology. The experimental L-asparaginase activity of 43.29 IU/ml was obtained at the optimum culture conditions of temperature 35 degrees C, initial pH 6.3, inoculum size 1% (v/v), agitation rate 140 rpm, and incubation time 58.5 h of the artificial neural network linked genetic algorithm, which was close to the predicted activity of 44.38 IU/ml. Characteristics of L-asparaginase production by A. terreus MTCC 1782 were studied in a 3 L bench-scale bioreactor.
Cultural Modelling: Literature review
2006-09-01
of mood and/or emotions. Our review did show some evidence that artificial intelligence research has tended to depict human decision making as...pp. 72-79). The Society for the Study of Artificial Intelligence and the Simulation of Behaviour (AISB). Halfill, T., Sundstrom, E., Nielsen, T. M...M. & Thagard, P. (2005). Changing personalities: Towards realistic virtual characters. Journal of Experimental & Theoretical Artificial Intelligence
Role of fibroblast-derived factors in the pathogenesis of melasma.
Byun, J W; Park, I S; Choi, G S; Shin, J
2016-08-01
The hyperactive melanocytes present in melasma skin are confined to the epidermis, but epidermal ablation to treat melasma pigmentation may lead to disease recurrence and aggravation. Melanocyte function is regulated by interactions between melanocytes and neighbouring cells such as keratinocytes and fibroblasts. Because melasma skin usually shows dermal changes after exposure to sunlight, we hypothesized that sun-damaged fibroblasts might play a crucial role in the pathogenesis of melasma. In this study, the melanogenic role of primary cultured fibroblasts from human melasma skin was investigated. We explored whether primary cultured fibroblasts from melasma tissue have a melanogenic function on cultured human epidermal melanocytes and artificial skin. The cytokine profile derived from fibroblasts and their effect on the pigmented epidermal equivalents were investigated. Fibroblasts from the melasma lesion and perilesional skin increased melanogenesis in cultured human epidermal melanocytes and in artificial skin. Fibroblasts from the melasma lesion and perilesional skin secreted more nerve growth factor (NGF)-β than those in normal buttock skin, and also increased melanogenesis and the expression level of NGF-β in cultured human epidermal melanocytes and artificial skin. These results suggest that fibroblasts may play a role in melanogenesis and the pathogenesis of melasma. © 2016 British Association of Dermatologists.
Mycoplasma Infection Alters Cancer Stem Cell Properties in Vitro.
Gedye, Craig; Cardwell, Tracy; Dimopoulos, Nektaria; Tan, Bee Shin; Jackson, Heather; Svobodová, Suzanne; Anaka, Matthew; Behren, Andreas; Maher, Christopher; Hofmann, Oliver; Hide, Winston; Caballero, Otavia; Davis, Ian D; Cebon, Jonathan
2016-02-01
Cancer cell lines can be useful to model cancer stem cells. Infection with Mycoplasma species is an insidious problem in mammalian cell culture. While investigating stem-like properties in early passage melanoma cell lines, we noted poorly reproducible results from an aliquot of a cell line that was later found to be infected with Mycoplasma hyorhinis. Deliberate infection of other early passage melanoma cell lines aliquots induced variable and unpredictable effects on expression of putative cancer stem cell markers, clonogenicity, proliferation and global gene expression. Cell lines established in stem cell media (SCM) were equally susceptible. Mycoplasma status is rarely reported in publications using cultured cells to study the cancer stem cell hypothesis. Our work highlights the importance of surveillance for Mycoplasma infection while using any cultured cells to interrogate tumor heterogeneity.
Yan, Shi-Kai; Wu, Yan-Wen; Liu, Run-Hui; Zhang, Wei-Dong
2007-01-01
Major bioactive components in various Calculus Bovis, including natural, artificial and in-vitro cultured Calculus Bovis, were comparatively studied. An approach of high-performance liquid chromatography coupled with ultraviolet and evaporative light scattering detections (HPLC/UV/ELSD) was established to simultaneously determinate six bioactive components thereof, including five bile acids (cholic acid, deoxycholic acid, ursodeoxycholic, chenodeoxycholic acid, hyodeoxycholic acid) and bilirubin. ELSD and UV detector were applied to detect bile acids and bilirubin respectively. The assay was performed on a C(18) column with water-acetonitrile gradient elution and the investigated constituents were authenticated by comparing retention times and mass spectra with those of reference compounds. The proposed method was applied to analyze twenty-one Calculus Bovis extraction samples, and produced data with acceptable linearity, precision, repeatability and accuracy. The result indicated the variations among Calculus Bovis samples under different developmental conditions. Artificial and in-vitro cultured Calculus Bovis, especially in-vitro cultured ones, which contain total bioactive constituents no less than natural products and have the best batch-to-batch uniformity, suffice to be used as substitutes of natural Calculus Bovis.
Chen, Lin; Liu, Yuetao; Guo, Qingfeng; Zheng, Qingxia; Zhang, Wancun
2018-05-11
A systematic study on the metabolome differences between wild Ophiocordyceps sinensis and artificial cultured Cordyceps militaris was conducted using liquid chromatography-mass spectrometry. Principal component analysis and orthogonal projection on latent structure-discriminant analysis results showed that C. militaris grown on solid rice medium (R-CM) and C. militaris grown on tussah pupa (T-CM) evidently separated and individually separated from wild O. sinensis, indicating metabolome difference among wild O. sinensis, R-CM and T-CM. The metabolome differences between R-CM and T-CM indicated that C. militaris could accommodate to culture medium by differential metabolic regulation. Hierarchical clustering analysis was further performed to cluster the differential metabolites and samples based on their metabolic similarity. The higher content of amino acids (pyroglutamic acid, glutamic acid, histidine, phenylalanine and arginine), unsaturated fatty acid (linolenic acid and linoleic acid), peptides, mannitol, adenosine and succinoadenosine in O. sinensis make it as an excellent choice as a traditional Chinese medicine for invigoration or nutritional supplementation. Similar compositions with O. sinensis and easy cultivation make artificially cultured C. militaris a possible alternative to O. sinensis. Copyright © 2018 John Wiley & Sons, Ltd.
Artificial Cells, Blood Substitutes, and Immobilization Biotechnology. Volume 22, Number 3, 1994.
1994-05-01
culture, microorganisms, enzymes, drugs, receptors, sorbents, immunosorbents and other biologically active molecules. (2) Artificial cells, microcapsules ...recombinant hemoglobin, and others. Chemistry, methods, in-vitro studies, in-vivo evaluations and clinical results. (4) Microencapsulation and other
Artificial Cells, Blood Substitutes, and Immobilization Biotechnology. Volume 22 Number 2, 1994.
1994-05-01
culture, microorganisms, enzymes, drugs, receptors, sorbents, immunosorbents and other biologically active molecules. (2) Artificial cells, microcapsules ...recombinant hemoglobin, and others. Chemistry, methods, in-vitro studies, in-vivo evaluations and clinical results. (4) Microencapsulation and other
Artificial Cells, Blood Substitutes, and Immobilization Biotechnology, Volume 22 Number 4, 1994.
1994-01-01
culture, microorganisms, enzymes, drugs, receptors, sorbents, immunosorbents and other biologically active molecules. (2) Artificial cells, microcapsules ...recombinant hemoglobin, and others. Chemistry, methods, in-vitro studies, in-vivo evaluations and clinical results. (4) Microencapsulation and other
The Release of Elements from Dental Casting Alloy into Cell-Culture Medium and Artificial Saliva
Can, Gülşen; Akpınar, Gül; Aydın, Ahmet
2007-01-01
Objectives The biocompatibility of dental casting alloys is a critical issue because these alloys are in long-term intimate contact with oral tissues. Since the biocompatibility of alloys is not completely known; the release of elements from the alloys has been studied. The aim of this study was to compare the elemental release from dental casting alloy during exposure to artificial saliva and cell-culture medium. Materials and Methods Twenty specimens made from Ni-Cr alloy were provided in the form of 5 mm diameter discs, 2 mm in thickness with a 7 mm stem attached to one face to facilitate handling. Ten of twenty samples were polished separately using a conventional technique. The remaining ten samples were left sandblasted with 50 μm Al203. Ten samples (5 polished, 5 sandblasted) were separately placed into cell-culture wells with Dulbecco’s Modified Eagle’s Medium. The other ten samples were placed separately into cell-culture wells with artificial saliva. The samples were subjected in contact with these medium for 30 days. These medium were collected every 7 days. The cell-culture medium and artificial saliva without alloy samples were subjected to elemental analyses as a control. At the end of the exposure time, Atomic Absorption Spectrometry (AAS) was used to determine the release of elements from the alloys into all collected medium. Statistical analyses were assessed with two-way ANOVA. Results In general, the elemental release occurred with in all medium. The elemental releases of sandblasted alloys were higher than polished alloys. Artificial saliva was found to cause more release from the samples. In both media, Ni released from polished and sandblasted alloys were higher than Cr and Mo. Conlusions The results suggest that the release of elements from the alloys might have correlated with the environments and the surface of dental alloy. PMID:19212482
The release of elements from dental casting alloy into cell-culture medium and artificial saliva.
Can, Gülşen; Akpınar, Gül; Aydın, Ahmet
2007-04-01
The biocompatibility of dental casting alloys is a critical issue because these alloys are in long-term intimate contact with oral tissues. Since the biocompatibility of alloys is not completely known; the release of elements from the alloys has been studied. The aim of this study was to compare the elemental release from dental casting alloy during exposure to artificial saliva and cell-culture medium. Twenty specimens made from Ni-Cr alloy were provided in the form of 5 mm diameter discs, 2 mm in thickness with a 7 mm stem attached to one face to facilitate handling. Ten of twenty samples were polished separately using a conventional technique. The remaining ten samples were left sandblasted with 50 mum Al(2)0(3). Ten samples (5 polished, 5 sandblasted) were separately placed into cell-culture wells with Dulbecco's Modified Eagle's Medium. The other ten samples were placed separately into cell-culture wells with artificial saliva. The samples were subjected in contact with these medium for 30 days. These medium were collected every 7 days. The cell-culture medium and artificial saliva without alloy samples were subjected to elemental analyses as a control. At the end of the exposure time, Atomic Absorption Spectrometry (AAS) was used to determine the release of elements from the alloys into all collected medium. Statistical analyses were assessed with two-way ANOVA. In general, the elemental release occurred with in all medium. The elemental releases of sandblasted alloys were higher than polished alloys. Artificial saliva was found to cause more release from the samples. In both media, Ni released from polished and sandblasted alloys were higher than Cr and Mo. The results suggest that the release of elements from the alloys might have correlated with the environments and the surface of dental alloy.
Developing and using artificial soils to analyze soil microbial processes
NASA Astrophysics Data System (ADS)
Gao, X.; Cheng, H. Y.; Boynton, L.; Masiello, C. A.; Silberg, J. J.
2017-12-01
Microbial diversity and function in soils are governed by soil characteristics such as mineral composition, particles size and aggregations, soil organic matter (SOM), and availability of nutrients and H2O. The spatial and temporal heterogeneity of soils creates a range of niches (hotspots) differing in the availability of O2, H2O, and nutrients, which shapes microbial activities at scales ranging from nanometer to landscape. Synthetic biologists often examine microbial response trigged by their environment conditions in nutrient-rich aqueous media using single strain microbes. While these studies provided useful insight in the role of soil microbes in important soil biogeochemical processes (e.g., C cycling, N cycling, etc.), the results obtained from the over-simplified model systems are often not applicable natural soil systems. On the contrary, soil microbiologists examine microbial processes in natural soils using longer incubation time. However, due to its physical, chemical and biological complexity of natural soils, it is often difficult to examine soil characteristics independently and understand how each characteristic influences soil microbial activities and their corresponding soil functioning. Therefore, it is necessary to bridge the gap and develop a model matrix to exclude unpredictable influences from the environment while still reliably mimicking real environmental conditions. The objective of this study is to design a range of ecologically-relevant artificial soils with varying texture (particle size distribution), structure, mineralogy, SOM content, and nutrient heterogeneity. We thoroughly characterize the artificial soils for pH, active surface area and surface morphology, cation exchange capacity (CEC), and water retention curve. We demonstrate the effectiveness of the artificial soils as useful matrix for microbial processes, such as microbial growth and horizontal gene transfer (HGT), using the gas-reporting biosensors recently developed in our lab.
Autonomy in robots and other agents.
Smithers, T
1997-06-01
The word "autonomous" has become widely used in artificial intelligence, robotics, and, more recently, artificial life and is typically used to qualify types of systems, agents, or robots: we see terms like "autonomous systems," "autonomous agents," and "autonomous robots." Its use in these fields is, however, both weak, with no distinctions being made that are not better and more precisely made with other existing terms, and varied, with no single underlying concept being involved. This ill-disciplined usage contrasts strongly with the use of the same term in other fields such as biology, philosophy, ethics, law, and human rights, for example. In all these quite different areas the concept of autonomy is essentially the same, though the language used and the aspects and issues of concern, of course, differ. In all these cases the underlying notion is one of self-law making and the closely related concept of self-identity. In this paper I argue that the loose and varied use of the term autonomous in artificial intelligence, robotics, and artificial life has effectively robbed these fields of an important concept. A concept essentially the same as we find it in biology, philosophy, ethics, and law, and one that is needed to distinguish a particular kind of agent or robot from those developed and built so far. I suggest that robots and other agents will have to be autonomous, i.e., self-law making, not just self-regulating, if they are to be able effectively to deal with the kinds of environments in which we live and work: environments which have significant large scale spatial and temporal invariant structure, but which also have large amounts of local spatial and temporal dynamic variation and unpredictability, and which lead to the frequent occurrence of previously unexperienced situations for the agents that interact with them.
NASA Astrophysics Data System (ADS)
Bhattachan, A.; BenDor, T.; Ardón, M.; Bernhardt, E. S.; Wright, J. P.; Emanuel, R. E.
2016-12-01
The Atlantic Coastal Plain of the United States has been altered drastically in the past century to support agriculture, real estate, and recreational activities. In a landscape with minimal hydraulic gradients and potentially large fluctuations in sea level, the effects of introducing artificial drainages (e.g., ditches and canals) on hydrological properties are often drastic and sometimes unpredictable. In this study, we focus on a portion of the outer coastal plain of North Carolina that ranges in elevation between 6 to -5 meters a.m.s.l. To this end, we use a high-resolution, Lidar-derived digital elevation model to study the effects of artificial drainages on landscape elevation, flow accumulation, and drainage density within an 800-km2 study area. Specifically, we use image-processing techniques to filter artificial drainages from the region and compare hydrologically relevant landscape metrics with and without these features. In general, artificial drainages lower land elevation, short-circuit otherwise natural flow paths and lead to increased ( 3 times) drainage density across the landscape. We also calculate a saltwater intrusion vulnerability index (SIVI), with and without canals and ditches, to investigate the contribution of this infrastructure to saltwater intrusion vulnerability in this low-lying coastal region. The SIVI represents the ability of the freshwater to impede the inland migration of saltwater during drought periods or as sea level rises. Our results show that the construction of artificial drainages would in fact lead to an increase in vulnerability to saltwater intrusion and this pattern is consistent across all four major land-cover (wetlands, agriculture, shrub and forest) in our study area. Thus, combined with extant saltwater impacts on freshwater-dependent landscapes across our study area, our findings are immediately relevant to this region and to similar coastal regions worldwide.
Electrogenic Single-Species Biocomposites as Anodes for Microbial Fuel Cells.
Kaiser, Patrick; Reich, Steffen; Leykam, Daniel; Willert-Porada, Monika; Greiner, Andreas; Freitag, Ruth
2017-07-01
Integration of electrogenic microorganisms remains a challenge in biofuel cell technology. Here, synthetic biocomposites ("artificial biofilms") are proposed. Bacteria (Shewanella oneidensis) are embedded in a hydrogel matrix (poly(vinyl alcohol)) via wet- and electrospinning, creating fibers and nonwoven gauzes. The bacteria remain viable and metabolically active. The performance is compared to S. oneidensis suspension cultures and "natural" biofilms. While lower than with the suspension cultures, the power output from the fuel cells with the artificial biofilms is higher than with the natural one. Handling, reproducibility, and stability are also better. Artificial biofilms can therefore contribute to resolving fundamental issues of design, scale up, and monosepsis in biofuel cell technology. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Conditions that impact artificial hybridization of Arachis hypogaea L.
USDA-ARS?s Scientific Manuscript database
Modern farming is dependent on continual development of improved cultivars and efficient cultural management practices. In addition, dissecting genetic components of heritable traits also relies on the development of large mapping populations. Artificial hybridization is the critical initial step ...
Engineering a Light-Attenuating Artificial Iris
Shareef, Farah J.; Sun, Shan; Kotecha, Mrignayani; Kassem, Iris; Azar, Dimitri; Cho, Michael
2016-01-01
Purpose Discomfort from light exposure leads to photophobia, glare, and poor vision in patients with congenital or trauma-induced iris damage. Commercial artificial iris lenses are static in nature to provide aesthetics without restoring the natural iris's dynamic response to light. A new photo-responsive artificial iris was therefore developed using a photochromic material with self-adaptive light transmission properties and encased in a transparent biocompatible polymer matrix. Methods The implantable artificial iris was designed and engineered using Photopia, a class of photo-responsive materials (termed naphthopyrans) embedded in polyethylene. Photopia was reshaped into annular disks that were spin-coated with polydimethylsiloxane (PDMS) to form our artificial iris lens of controlled thickness. Results Activated by UV and blue light in approximately 5 seconds with complete reversal in less than 1 minute, the artificial iris demonstrates graded attenuation of up to 40% of visible and 60% of UV light. There optical characteristics are suitable to reversibly regulate the incident light intensity. In vitro cell culture experiments showed up to 60% cell death within 10 days of exposure to Photopia, but no significant cell death observed when cultured with the artificial iris with protective encapsulation. Nuclear magnetic resonance spectroscopy confirmed these results as there was no apparent leakage of potentially toxic photochromic material from the ophthalmic device. Conclusions Our artificial iris lens mimics the functionality of the natural iris by attenuating light intensity entering the eye with its rapid reversible change in opacity and thus potentially providing an improved treatment option for patients with iris damage. PMID:27116547
Engineering a Light-Attenuating Artificial Iris.
Shareef, Farah J; Sun, Shan; Kotecha, Mrignayani; Kassem, Iris; Azar, Dimitri; Cho, Michael
2016-04-01
Discomfort from light exposure leads to photophobia, glare, and poor vision in patients with congenital or trauma-induced iris damage. Commercial artificial iris lenses are static in nature to provide aesthetics without restoring the natural iris's dynamic response to light. A new photo-responsive artificial iris was therefore developed using a photochromic material with self-adaptive light transmission properties and encased in a transparent biocompatible polymer matrix. The implantable artificial iris was designed and engineered using Photopia, a class of photo-responsive materials (termed naphthopyrans) embedded in polyethylene. Photopia was reshaped into annular disks that were spin-coated with polydimethylsiloxane (PDMS) to form our artificial iris lens of controlled thickness. Activated by UV and blue light in approximately 5 seconds with complete reversal in less than 1 minute, the artificial iris demonstrates graded attenuation of up to 40% of visible and 60% of UV light. There optical characteristics are suitable to reversibly regulate the incident light intensity. In vitro cell culture experiments showed up to 60% cell death within 10 days of exposure to Photopia, but no significant cell death observed when cultured with the artificial iris with protective encapsulation. Nuclear magnetic resonance spectroscopy confirmed these results as there was no apparent leakage of potentially toxic photochromic material from the ophthalmic device. Our artificial iris lens mimics the functionality of the natural iris by attenuating light intensity entering the eye with its rapid reversible change in opacity and thus potentially providing an improved treatment option for patients with iris damage.
U-series dating of impure carbonates: An isochron technique using total-sample dissolution
Bischoff, J.L.; Fitzpatrick, J.A.
1991-01-01
U-series dating is a well-established technique for age determination of Late Quaternary carbonates. Materials of sufficient purity for nominal dating, however, are not as common as materials with mechanically inseparable aluminosilicate detritus. Detritus contaminates the sample with extraneous Th. We propose that correction for contamination is best accomplished with the isochron technique using total sample dissolution (TSD). Experiments were conducted on artificial mixtures of natural detritus and carbonate and on an impure carbonate of known age. Results show that significant and unpredictable transfer of radionuclides occur from the detritus to the leachate in commonly used selective leaching procedures. The effects of correcting via leachate-residue pairs and isochron plots were assessed. Isochrons using TSD gave best results, followed by isochron plots of leachates only. ?? 1991.
29 CFR 4022.27 - Phase-in of guarantee of unpredictable contingent event benefits.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 29 Labor 9 2014-07-01 2014-07-01 false Phase-in of guarantee of unpredictable contingent event... Guaranteed Benefits § 4022.27 Phase-in of guarantee of unpredictable contingent event benefits. (a) Scope... event benefit (UCEB) and that is payable with respect to an unpredictable contingent event (UCE) that...
Three dimensional optic tissue culture and process
NASA Technical Reports Server (NTRS)
Spaulding, Glenn F. (Inventor); Prewett, Tacey L. (Inventor); Goodwin, Thomas J. (Inventor); Francis, Karen M. (Inventor); Cardwell, Delmar R. (Inventor); Oconnor, Kim (Inventor); Fitzgerald, Wendy S. (Inventor); Aten, Laurie A. (Inventor)
1994-01-01
A process for artificially producing three-dimensional optic tissue has been developed. The optic cells are cultured in a bioreactor at low shear conditions. The tissue forms normal, functional tissue organization and extracellular matrix.
Miyauchi, Shunsuke; Yonetani, Tsutomu; Yuki, Takayuki; Tomio, Ayako; Bamba, Takeshi; Fukusaki, Eiichiro
2017-02-01
For an experimental model to elucidate the relationship between light quality during plant culture conditions and plant quality of crops or vegetables, we cultured tea plants (Camellia sinensis) and analyzed their leaves as tea material. First, metabolic profiling of teas from a tea contest in Japan was performed with gas chromatography/mass spectrometry (GC/MS), and then a ranking predictive model was made which predicted tea rankings from their metabolite profile. Additionally, the importance of some compounds (glutamine, glutamic acid, oxalic acid, epigallocatechin, phosphoric acid, and inositol) was elucidated for measurement of the quality of tea leaf. Subsequently, tea plants were cultured in artificial conditions to control these compounds. From the result of prediction by the ranking predictive model, the tea sample supplemented with ultraviolet-A (315-399 nm) showed the highest ranking. The improvement in quality was thought to come from the high amino-acid and decreased epigallocatechin content in tea leaves. The current study shows the use and value of metabolic profiling in the field of high-quality crops and vegetables production that has been conventionally evaluated by human sensory analysis. Metabolic profiling enables us to form hypothesis to understand and develop high quality plant cultured under artificial condition. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
Non-autonomous equations with unpredictable solutions
NASA Astrophysics Data System (ADS)
Akhmet, Marat; Fen, Mehmet Onur
2018-06-01
To make research of chaos more amenable to investigating differential and discrete equations, we introduce the concepts of an unpredictable function and sequence. The topology of uniform convergence on compact sets is applied to define unpredictable functions [1,2]. The unpredictable sequence is defined as a specific unpredictable function on the set of integers. The definitions are convenient to be verified as solutions of differential and discrete equations. The topology is metrizable and easy for applications with integral operators. To demonstrate the effectiveness of the approach, the existence and uniqueness of the unpredictable solution for a delay differential equation are proved as well as for quasilinear discrete systems. As a corollary of the theorem, a similar assertion for a quasilinear ordinary differential equation is formulated. The results are demonstrated numerically, and an application to Hopfield neural networks is provided. In particular, Poincaré chaos near periodic orbits is observed. The completed research contributes to the theory of chaos as well as to the theory of differential and discrete equations, considering unpredictable solutions.
Poincaré chaos and unpredictable functions
NASA Astrophysics Data System (ADS)
Akhmet, Marat; Fen, Mehmet Onur
2017-07-01
The results of this study are continuation of the research of Poincaré chaos initiated in the papers (M. Akhmet and M.O. Fen, Commun Nonlinear Sci Numer Simulat 40 (2016) 1-5; M. Akhmet and M.O. Fen, Turk J Math, doi:10.3906/mat-1603-51, in press). We focus on the construction of an unpredictable function, continuous on the real axis. As auxiliary results, unpredictable orbits for the symbolic dynamics and the logistic map are obtained. By shaping the unpredictable function as well as Poisson function we have performed the first step in the development of the theory of unpredictable solutions for differential and discrete equations. The results are preliminary ones for deep analysis of chaos existence in differential and hybrid systems. Illustrative examples concerning unpredictable solutions of differential equations are provided.
Das Ende der Nacht [The End of the Night (2nd enlarged ed.)
NASA Astrophysics Data System (ADS)
Posch, Thomas; Hölker, Franz; Uhlmann, Thomas; Freyhoff, Anja
2013-09-01
We provide provide an overview of the history of lighting and of the problems arising from artificial lighting. The book covers the following topics: A brief history of light (ch. 1); night and light in cultural history (ch. 2); light pollution in central Europe (ch. 3); Moths and artificial lights (ch. 4); Artificial lighting and birds (ch. 5); Ocean turtles as victims of beach lighting (ch. 6); Moon light as a zeitgeber for the marine fauna (ch. 7); the influence of artificial light at night on freshwater ecology (ch. 8); artificial light and human health (ch. 9); the loss of the night in a 24 hours society (ch. 10).
Bringing Artificial Gravity into the Classroom
NASA Astrophysics Data System (ADS)
Thompson, Grant; Aning, Isaac
2018-01-01
We recently conducted an experimental test of artificial gravity by placing various species of plants in centrifuges and analyzed the plants’ germination and growth. This research project incorporated several topics covered in undergraduate astronomy, biology, and physics courses. Given the interest of introductory astronomy students in artificial gravity and their pre-existing images of applications such as rotating spacecraft from pop culture, the results of the experiment may provide a gateway to discuss artificial gravity beyond teaching the traditional examples of Newton’s laws. We will discuss the experiment in detail and provide suggestions for how the experiment could be incorporated into your classroom.
ERIC Educational Resources Information Center
Boorstin, Daniel J.
These remarks suggest that, although the world's cultures--and the culture of books--may be defined by languages, by traditions, and by historical movements, they are not confined by national boundaries: all boundaries in the world of culture and ideas are artificial and all are doomed to be dissolved. Since all culture belongs to all people,…
Rakers, Sebastian; Klinger, Matthias; Kruse, Charli; Gebert, Marina
2011-12-01
Here, we report the establishment of a permanent skin cell culture from rainbow trout (Oncorhynchus mykiss). The cells of the fish skin cell culture could be propagated over 60 passages so far. Furthermore, we show for the first time that it is possible to integrate freshly harvested rainbow trout scales into this new fish skin cell culture. We further demonstrated that epithelial cells derived from the scales survived in the artificial micro-environment of surrounding fibroblast-like cells. Also, antibody staining indicated that both cell types proliferated and started to build connections with the other cell type. It seems that it is possible to generate an 'artificial skin' with two different cell types. This could lead to the development of a three-dimensional test system, which might be a better in vitro representative of fish skin in vivo than individual skin cell lines. Copyright © 2011 Elsevier GmbH. All rights reserved.
Marquet, Pablo A.; Santoro, Calogero M.; Latorre, Claudio; Standen, Vivien G.; Abades, Sebastián R.; Rivadeneira, Marcelo M.; Arriaza, Bernardo; Hochberg, Michael E.
2012-01-01
The emergence of complex cultural practices in simple hunter-gatherer groups poses interesting questions on what drives social complexity and what causes the emergence and disappearance of cultural innovations. Here we analyze the conditions that underlie the emergence of artificial mummification in the Chinchorro culture in the coastal Atacama Desert in northern Chile and southern Peru. We provide empirical and theoretical evidence that artificial mummification appeared during a period of increased coastal freshwater availability and marine productivity, which caused an increase in human population size and accelerated the emergence of cultural innovations, as predicted by recent models of cultural and technological evolution. Under a scenario of increasing population size and extreme aridity (with little or no decomposition of corpses) a simple demographic model shows that dead individuals may have become a significant part of the landscape, creating the conditions for the manipulation of the dead that led to the emergence of complex mortuary practices. PMID:22891345
Design-Based Intervention Research as the Science of the Doubly Artificial
ERIC Educational Resources Information Center
Cole, Michael; Packer, Martin
2016-01-01
This article uses a variety of principles of cultural-historical activity theory to extend Herbert Simon's (1996) insight into the inherent linkage between the creation of artifacts and design. We argue that design research must grapple with the doubly artificial, as the classrooms in which many educational designs are implemented are themselves…
Rahiman, F; Pool, E J
2014-01-01
This article investigates the effects of commercially available artificial (aspartame, saccharin, sucralose) and natural sweeteners (brown sugar, white sugar, molasses) on the immune system. Human whole blood cultures were incubated with various sweeteners and stimulated in vitro with either phytohemagglutinin or endotoxin. Harvested supernatants were screened for cytotoxicity and cytokine release. Results showed that none of the artificial or natural sweeteners proved to be cytotoxic, indicating that no cell death was induced in vitro. The natural sweetener, sugar cane molasses (10 ug/mL), enhanced levels of the inflammatory biomarker IL-6 while all artificial sweeteners (10 ug/mL) revealed a suppressive effect on IL-6 secretion (P < 0.001). Exposure of blood cells to sucralose-containing sweeteners under stimulatory conditions reduced levels of the biomarker of humoral immunity, Interleukin-10 (P < 0.001). The cumulative suppression of Interleukin-6 and Interleukin-10 levels induced by sucralose may contribute to the inability in mounting an effective humoral response when posed with an exogenous threat.
Three Dimensional Optic Tissue Culture and Process
NASA Technical Reports Server (NTRS)
OConnor, Kim C. (Inventor); Spaulding, Glenn F. (Inventor); Goodwin, Thomas J. (Inventor); Aten, Laurie A. (Inventor); Francis, Karen M. (Inventor); Caldwell, Delmar R. (Inventor); Prewett, Tacey L. (Inventor); Fitzgerald, Wendy S. (Inventor)
1999-01-01
A process for artificially producing three-dimensional optic tissue has been developed. The optic cells are cultured in a bioireactor at low shear conditions. The tissue forms as normal, functional tissue grows with tissue organization and extracellular matrix formation.
A Model of Mental State Transition Network
NASA Astrophysics Data System (ADS)
Xiang, Hua; Jiang, Peilin; Xiao, Shuang; Ren, Fuji; Kuroiwa, Shingo
Emotion is one of the most essential and basic attributes of human intelligence. Current AI (Artificial Intelligence) research is concentrating on physical components of emotion, rarely is it carried out from the view of psychology directly(1). Study on the model of artificial psychology is the first step in the development of human-computer interaction. As affective computing remains unpredictable, creating a reasonable mental model becomes the primary task for building a hybrid system. A pragmatic mental model is also the fundament of some key topics such as recognition and synthesis of emotions. In this paper a Mental State Transition Network Model(2) is proposed to detect human emotions. By a series of psychological experiments, we present a new way to predict coming human's emotions depending on the various current emotional states under various stimuli. Besides, people in different genders and characters are taken into consideration in our investigation. According to the psychological experiments data derived from 200 questionnaires, a Mental State Transition Network Model for describing the transitions in distribution among the emotions and relationships between internal mental situations and external are concluded. Further more the coefficients of the mental transition network model were achieved. Comparing seven relative evaluating experiments, an average precision rate of 0.843 is achieved using a set of samples for the proposed model.
Challenges facing the distribution of an artificial-intelligence-based system for nursing.
Evans, S
1985-04-01
The marketing and successful distribution of artificial-intelligence-based decision-support systems for nursing face special barriers and challenges. Issues that must be confronted arise particularly from the present culture of the nursing profession as well as the typical organizational structures in which nurses predominantly work. Generalizations in the literature based on the limited experience of physician-oriented artificial intelligence applications (predominantly in diagnosis and pharmacologic treatment) must be modified for applicability to other health professions.
Track structure model for damage to mammalian cell cultures during solar proton events
NASA Technical Reports Server (NTRS)
Cucinotta, F. A.; Wilson, J. W.; Townsend, L. W.; Shinn, J. L.; Katz, R.
1992-01-01
Solar proton events (SPEs) occur infrequently and unpredictably, thus representing a potential hazard to interplanetary space missions. Biological damage from SPEs will be produced principally through secondary electron production in tissue, including important contributions due to delta rays from nuclear reaction products. We review methods for estimating the biological effectiveness of SPEs using a high energy proton model and the parametric cellular track model. Results of the model are presented for several of the historically largest flares using typical levels and body shielding.
de-Graft Aikins, Ama
2014-01-01
Ghanaian women's food beliefs and practices during pregnancy and the scope for developing more effective maternal health interventions were explored in this study. Thirty-five multiethnic Ghanaian women between the ages of 29 and 75 were interviewed about pregnancy food beliefs and practices. I show that, based on the data analysis, their knowledge about food was drawn from lifeworlds (family and friends), educational settings, health professionals, mass media, and body-self knowledge (unique pregnancy experiences). Core lay ideas converged with expert knowledge on maternal health nutrition. Multiple external factors (e.g., economics, cultural representations of motherhood) and internal factors (e.g., the unpredictable demands of the pregnant body) influenced pregnancy food practices. I suggest and discuss a need for culturally situated multilevel interventions.
Grillon, Christian; Baas, Johanna M P; Cornwell, Brian; Johnson, Linda
2006-10-01
Sustained anxiety can be modeled using context conditioning, which can be studied in a virtual reality environment. Unpredictable stressors increase context conditioning in animals. This study examined context conditioning to predictable and unpredictable shocks in humans using behavioral avoidance, potentiated startle, and subjective reports of anxiety. Subjects were guided through three virtual rooms (no-shock, predictable, unpredictable contexts). Eight-sec duration colored lights served as conditioned stimuli (CS). During acquisition, no shock was administered in the no-shock context. Shocks were paired with the CS in the predictable context and were administered randomly in the unpredictable context. No shock was administered during extinction. Startle stimuli were delivered during CS and between CS to assess cued and context conditioning, respectively. To assess avoidance, subjects freely navigated into two of the three contexts to retrieve money. Startle between CS was potentiated in the unpredictable context compared to the two other contexts. Following acquisition, subjects showed a strong preference for the no-shock context and avoidance of the unpredictable context. Consistent with animal data, context conditioning is increased by unpredictability. These data support virtual reality as a tool to extend research on physiological and behavioral signs of fear and anxiety in humans.
Specialized Veterinary Manpower Needs through 1990,
1982-01-01
vaccines and diagnostic tests; and the increased technical sophistication in artificial insemination , embryo culture and transplantation, and hormonal...are included. Artificial insemination , synchronization of estrus, endocrine therapy, spermatozoan and ovum genetic engineering, and ovum and embryo...hospital facility surrounded by satellite clinics that offer restricted medical and surgical services. 26 Qualified animal-health technicians are used to a
Vertical leadership in highly complex and unpredictable health systems.
Till, Alex; Dutta, Nina; McKimm, Judy
2016-08-02
This article explores how the concept of vertical leadership development might help health organizations cope with and thrive within highly complex and unpredictable health systems, looking at concepts of VUCA (volatility, uncertainty, complexity and ambiguity) and RUPT (rapid, unpredictable, paradoxical and tangled).
Social influence and the Matthew mechanism: The case of an artificial cultural market
NASA Astrophysics Data System (ADS)
Bask, Miia; Bask, Mikael
2014-10-01
We show that the Matthew effect, or Matthew mechanism, was present in the artificial cultural market Music Lab in one-fourth of the “worlds” when social influence between individuals was allowed, whereas this effect was not present in the “world” that disallowed social influence between individuals. We also sketch on a class of social network models, derived from social influence theory, that may generate the Matthew effect. Thus, we propose a theoretical framework that may explain why the most popular songs could be much more popular, and the least popular songs could be much less popular, than when disallowing social influence between individuals.
A New Arbiter PUF for Enhancing Unpredictability on FPGA
Machida, Takanori; Yamamoto, Dai; Iwamoto, Mitsugu; Sakiyama, Kazuo
2015-01-01
In general, conventional Arbiter-based Physically Unclonable Functions (PUFs) generate responses with low unpredictability. The N-XOR Arbiter PUF, proposed in 2007, is a well-known technique for improving this unpredictability. In this paper, we propose a novel design for Arbiter PUF, called Double Arbiter PUF, to enhance the unpredictability on field programmable gate arrays (FPGAs), and we compare our design to conventional N-XOR Arbiter PUFs. One metric for judging the unpredictability of responses is to measure their tolerance to machine-learning attacks. Although our previous work showed the superiority of Double Arbiter PUFs regarding unpredictability, its details were not clarified. We evaluate the dependency on the number of training samples for machine learning, and we discuss the reason why Double Arbiter PUFs are more tolerant than the N-XOR Arbiter PUFs by evaluating intrachip variation. Further, the conventional Arbiter PUFs and proposed Double Arbiter PUFs are evaluated according to other metrics, namely, their uniqueness, randomness, and steadiness. We demonstrate that 3-1 Double Arbiter PUF archives the best performance overall. PMID:26491720
Nelson, Brady D; Hajcak, Greg
2017-02-01
There is growing evidence that heightened sensitivity to unpredictability is a core mechanism of anxiety disorders. In adults, multiple anxiety disorders have been associated with a heightened startle reflex in anticipation of unpredictable threat. Child and adolescent anxiety has been linked to an increased startle reflex across baseline, safety, and threat conditions. However, it is unclear whether anxiety in youth is related to the startle reflex as a function of threat predictability. In a sample of 90 8 to 14 year-old girls, the present study examined the association between anxiety symptom dimensions and startle potentiation during a no, predictable, and unpredictable threat task. Depression symptom dimensions were also examined given their high comorbidity with anxiety and mixed relationship with the startle reflex and sensitivity to unpredictability. To assess current symptoms, participants completed the self-report Screen for Child Anxiety Related Emotional Disorders and Children's Depression Inventory. Results indicated that social phobia symptoms were associated with heightened startle potentiation in anticipation of unpredictable threat and attenuated startle potentiation in anticipation of predictable threat. Negative mood and negative self-esteem symptoms were associated with attenuated and heightened startle potentiation in anticipation of unpredictable threat, respectively. All results remained significant after controlling for the other symptom dimensions. The present study provides initial evidence that anxiety and depression symptom dimensions demonstrate unique associations with the startle reflex in anticipation of unpredictable threat in children and adolescents.
Nelson, Brady D.; Hajcak, Greg
2016-01-01
There is growing evidence that heightened sensitivity to unpredictability is a core mechanism of anxiety disorders. In adults, multiple anxiety disorders have been associated with a heightened startle reflex in anticipation of unpredictable threat. Child and adolescent anxiety has been linked to an increased startle reflex across baseline, safety, and threat conditions. However, it is unclear whether anxiety in youth is related to the startle reflex as a function of threat predictability. In a sample of 90 8 to 14 year-old girls, the present study examined the association between anxiety symptom dimensions and startle potentiation during a no, predictable, and unpredictable threat task. Depression symptom dimensions were also examined given their high comorbidity with anxiety and mixed relationship with the startle reflex and sensitivity to unpredictability. To assess current symptoms, participants completed the self-report Screen for Child Anxiety Related Emotional Disorders and Children’s Depression Inventory. Results indicated that social phobia symptoms were associated with heightened startle potentiation in anticipation of unpredictable threat and attenuated startle potentiation in anticipation of predictable threat. Negative mood and negative self-esteem symptoms were associated with attenuated and heightened startle potentiation in anticipation of unpredictable threat, respectively. All results remained significant after controlling for the other symptom dimensions. The present study provides initial evidence that anxiety and depression symptom dimensions demonstrate unique associations with the startle reflex in anticipation of unpredictable threat in children and adolescents. PMID:27224989
Aesthetics and representation in holography
NASA Astrophysics Data System (ADS)
Kac, Eduardo
1995-02-01
Every medium has a code, a set of rules or conventions according to which determined elements are organized into a signifying system. The English language is a code as is perspective in painting and photography. In the first case, the elements are phonemes organized into words and sentences according to a social convention: the syntax of English. In the second case, the elements are dots and lines organized into pictures according to a geometric method. An artist or movement can break the conventions of the medium, as has done Cezanne with painting, Moholy-Nagy with photography and cummings with the English idiom in poetry, and create new elements and rules for combining them. If this is done, the level of predictability (or conventionality) is lowered and unpredictability is increased -- becoming more difficult for the immediate audience to understand it. But once these new rules are learned and the ideas behind them widely understood, the level of unpredictability is lowered and they become new conventions that can be accepted by the audience. Holographic artists exploring the medium -- as opposed to advertisers using holography, who favor a high level of predictability -- are breaking several visual and cultural conventions. As a matter of fact, holography is so new that many questions are left open about the nature of the medium. Therefore, any attempt to clarify the issues raised by holography on a cultural level has a prospective (and not conclusive) tone, concentrating more thoroughly on general points and on the promise of its potentialities than on the records of its historical achievements so far.
Otlewska, Anna; Adamiak, Justyna; Gutarowska, Beata
2014-01-01
As a result of their unpredictable ability to adapt to varying environmental conditions, microorganisms inhabit different types of biological niches on Earth. Owing to the key role of microorganisms in many biogeochemical processes, trends in modern microbiology emphasize the need to know and understand the structure and function of complex microbial communities. This is particularly important if the strategy relates to microbial communities that cause biodeterioration of materials that constitute our cultural heritage. Until recently, the detection and identification of microorganisms inhabiting objects of cultural value was based only on cultivation-dependent methods. In spite of many advantages, these methods provide limited information because they identify only viable organisms capable of growth under standard laboratory conditions. However, in order to carry out proper conservation and renovation, it is necessary to know the complete composition of microbial communities and their activity. This paper presents and characterizes modern techniques such as genetic fingerprinting and clone library construction for the assessment of microbial diversity based on molecular biology. Molecular methods represent a favourable alternative to culture-dependent methods and make it possible to assess the biodiversity of microorganisms inhabiting technical materials and cultural heritage objects.
NASA Astrophysics Data System (ADS)
Liu, Liming; Du, Rongbin; Zhang, Xiaoling; Dong, Shuanglin; Sun, Shichun
2017-01-01
Periphytic biofilms in aquaculture waters are thought to improve water quality, provide an additional food source, and improve the survival and growth of some reared animals. In the Asia- Pacific region, particularly in China, artificial reefs are commonly used in the commercial farming of sea cucumbers. However, few studies have examined the epilithic biofilms on the artificial reefs. To gain a better understanding of the succession of epilithic biofilms and their ecological processes in sea cucumber culture waters, two experiments were conducted in culture waters of the sea cucumber Apostichopus japonicus in Rongcheng, China, using artificial test panels. On the test panels of succession experiment, more than 67 species were identified in the biofilms. On the test panels of seasonal variation experiment, more than 46 species were recorded in the biofilms. In both experiments, communities of epilithic biofilms were dominated by diatoms, green algae and the annelid Spirorbis sp. In the initial colonization, the dominant diatoms were Cocconeis sp., Amphora spp. and Nitzschia closterium in June, which were succeeded by species of Navicula, Cocconeis and Nitzschia (July to September), and then by Licmophora abbreviata, Nitzschia closterium and Synedra spp. in the following months. A diatom bloom in the autumn and filamentous green algae burst in the summer were also observed. Ecological indices well annotated the succession and seasonal changes in epilithic communities. Multidimensional scaling (MDS) analysis found significant differences in diatom community composition among months and seasons. Fast growth of biofilms was observed in the summer and autumn, whereas the biomass of summer biofilms was largely made up of filamentous green algae. Present results show that the components of epilithic biofilms are mostly optimal foods of A. japonicus, suggesting that biofilms on artificial reefs may contribute important nutritional sources for sea cucumbers during their growth seasons. Future works should include quantitative determination of the contribution of epilithic biofilms to the diet of A. japonicus, potential roles of epilithic biofilms in regulating the water quality of sea cucumber ponds, and the regulation of epilithic biofilms in sea cucumber culture ponds.
Huang, Jianming; Chen, Fengrong; Jian, Guojian; Ye, Zhiyang; Wang, Zimin; Liu, Haoyuan; Kang, Yifan
2015-01-01
Ligament reconstruction is an effective therapy for anterior cruciate ligament (ACL) rupture. Polyethylene terephthalate (PET) artificial ligaments have recently gained popularity in clinical ACL reconstruction for its advantage in the improvement of keen function. However, the application of PET in clinical treatment is limited by its poor bioactivity and biocompatibility. Recently, bone marrow-derived mesenchymal stem cells (BMSCs) have been widely studied in regenerative medical therapy due to their multi-lineage differentiation. Previous study also indicated that BMSCs may promote the healing of tendon-bone interface of injured ligament. We speculate that BMSCs may enhance the curative effect of PET artificial ligament on the tendon-bone-healing in ligament reconstruction. In this study, the PET materials were first modified with sodium hydroxide hydrolysis and GRGDSPC peptide which was able to improve its bioactivity and biocompatibility. Then, the effects of modified PET materials on the adhesion, proliferation and differentiation of BMSCs were examined. The in vitro co-culture of BMSCs and modified PET showed the modified PET promoted the adhesion, proliferation and differentiation of BMSCs. Further, the effect of culture complex of BMSCs and modified PET artificial ligament co-culture system on the injured ligament reconstruction was investigated in vivo. Results showed not only better growth and differentiation of BMSCs but also satisfactory healing of the injured ligament was observed after implantation of this culture complex into the injured ligament of rabbits. Our study provides a brand-new solution for ACL reconstruction. PMID:26221227
Selection of diet for culture of juvenile silver pomfret, Pampus argenteus
NASA Astrophysics Data System (ADS)
Peng, Shiming; Shi, Zhaohong; Yin, Fei; Sun, Peng; Wang, Jiangang
2012-03-01
Juvenile silver pomfret, Pampus argenteus, was grown in culture tanks for 9 weeks on four different diets, and their effects on fish growth, digestive enzyme activity, and body composition were assessed. The feeding regime was as follows: Diet 1: fish meat; Diet 2: fish meat+artificial feed; Diet 3: fish meat+artificial feed+Agamaki clam meat; Diet 4: fish meat+artificial feed+Agamaki clam+copepods. The greatest weight gain was associated with Diet 4, while the lowest weight gain was associated with Diet 1. No significant difference was observed in weight gain between fish receiving Diet 2 and Diet 3. Specific growth rate followed similar trends as weight gain. The feed conversion ratio (FCR) of fish fed Diet 1 was significantly higher than the other fish groups, but no significant differences were observed in FCRs of fish fed Diet 2, Diet 3 or Diet 4. There was also no significant difference in the hepatosomatic index (HSI) between the four diets. For fish that received Diets 2-4, containing artificial feed, higher protease activities were detected. A higher lipid content of the experimental diets also significantly increased lipase activities and body lipid content. No significant differences in amylase activity or body protein content were found between Diets 1-4. In conclusion, a variety of food components, including copepods and artificial feed, in the diet of silver pomfret significantly increased digestive enzyme activity and could improve growth performance.
Hirshorn, Elizabeth A.; Fiez, Julie A.
2017-01-01
Reading and writing are cultural inventions that have become vital skills to master in modern society. Unfortunately, writing systems are not equally learnable and many individuals struggle to become proficient readers. Languages and their writing systems often have co-varying characteristics, due to both psycholinguistic and socio-cultural forces. This makes it difficult to determine the source of cross-linguistic differences in reading and writing. Nonetheless, it is important to make progress on this issue: a more precise understanding of the factors that affect reading disparities should improve reading instruction theory and practice, and the diagnosis and treatment of reading disorders. In this review, we consider the value of artificial orthographies as a tool for unpacking the factors that create cognitive and neural differences in reading acquisition and skill. We do so by focusing on one dimension that differs among writing systems: grain size. Grain size, or the unit of spoken language that is mapped onto a visual graph, is thought to affect learning, but its impact is still not well understood. We review relevant literature about cross-linguistic writing system differences, the benefits of using artificial orthographies as a research tool, and our recent work with an artificial alphasyllabic writing system for English. We conclude that artificial orthographies can be used to elucidate cross-linguistic principles that affect reading and writing. PMID:28280288
Park, M; Costa, E L V; Maciel, A T; Barbosa, E V S; Hirota, A S; Schettino, G de P; Azevedo, L C P
2014-11-01
Transmembrane pressure drop reflects the resistance of an artificial lung system to blood transit. Decreased resistance (low transmembrane pressure drop) enhances blood flow through the oxygenator, thereby, enhancing gas exchange efficiency. This study is part of a previous one where we observed the behaviour and the modulation of blood pressure drop during the passage of blood through artificial lung membranes. Before and after the induction of multi-organ dysfunction, the animals were instrumented and analysed for venous-venous extracorporeal membrane oxygenation, using a pre-defined sequence of blood flows. Blood flow and revolutions per minute (RPM) of the centrifugal pump varied in a linear fashion. At a blood flow of 5.5 L/min, pre- and post-pump blood pressures reached -120 and 450 mmHg, respectively. Transmembrane pressures showed a significant spread, particularly at blood flows above 2 L/min; over the entire range of blood flow rates, there was a positive association of pressure drop with blood flow (0.005 mmHg/mL/minute of blood flow) and a negative association of pressure drop with temperature (-4.828 mmHg/(°Celsius). These associations were similar when blood flows of below and above 2000 mL/minute were examined. During its passage through the extracorporeal system, blood is exposed to pressure variations from -120 to 450 mmHg. At high blood flows (above 2 L/min), the drop in transmembrane pressure becomes unpredictable and highly variable. Over the entire range of blood flows investigated (0-5500 mL/min), the drop in transmembrane pressure was positively associated with blood flow and negatively associated with body temperature. © The Author(s) 2014.
Serious Use of a Serious Game for Language Learning
ERIC Educational Resources Information Center
Johnson, W. Lewis
2010-01-01
The Tactical Language and Culture Training System (TLCTS) helps learners acquire basic communicative skills in foreign languages and cultures. Learners acquire communication skills through a combination of interactive lessons and serious games. Artificial intelligence plays multiple roles in this learning environment: to process the learner's…
IN VITRO CULTURING OF THE PREDATORY SOIL NEMATODE CLARKUS PAPILLATUS
Clarkus papillatus is a widely distributed predatory soil nematode and is of interest in the study of soil ecology, yet very little information exists on its in vitro culturing. In this investigation, an artificial environment was created to maintain C. papillatus for multi-gener...
Nogueira, Selene S C; Abreu, Shauana A; Peregrino, Helderes; Nogueira-Filho, Sérgio L G
2014-01-01
Some authors have suggested that environmental unpredictability, accompanied by some sort of signal for behavioral conditioning, can boost activity or foster exploratory behavior, which may increase post-release success in re-introduction programs. Thus, using white-lipped peccary (Tayassu pecari), a vulnerable Neotropical species, as a model, we evaluated an unpredictable feeding schedule. Associating this with the effect of classical conditioning on behavioral activities, we assessed the inclusion of this approach in pre-release training protocols. The experimental design comprised predictable feeding phases (control phases: C1, C2 and C3) and unpredictable feeding phases (U1- signaled and U2- non-signaled). The animals explored more during the signaled and non-signaled unpredictable phases and during the second control phase (C2) than during the other two predictable phases (C1 and C3). The peccaries also spent less time feeding during the signaled unpredictable phase (U1) and the following control phase (C2) than during the other phases. Moreover, they spent more time in aggressive encounters during U1 than the other experimental phases. However, the animals did not show differences in the time they spent on affiliative interactions or in the body weight change during the different phases. The signaled unpredictability, besides improving foraging behavior, showing a prolonged effect on the next control phase (C2), also increased the competition for food. The signaled feeding unpredictability schedule, mimicking wild conditions by eliciting the expression of naturalistic behaviors in pre-release training, may be essential to fully prepare them for survival in the wild.
Fontanilla, M R; Casadiegos, S; Bustos, R H; Patarroyo, M A
2018-04-24
Cytokines, chemokines, and growth and remodeling factors orchestrate wound healing when skin damage occurs. During early stages, when the wound is still open, detection and quantification of these compounds might provide biomarkers of skin wound healing, which could aid to complete the scenario provided by clinical follow-up data and histological and histomorphometric analyses. This work assessed and compared the healing of full-thickness skin wounds grafted with artificial dermis made with autologous skin fibroblasts and unidirectional or multidirectional type I collagen scaffolds to test this hypothesis. Biomarkers of healing were detected and quantified in the culture medium of artificial dermis and exudates from the grafted wounds. Clinical follow-up of animals and histological and histomorphometric analysis showed differences in graft integration, wound closure, and histological and histomorphometric parameters. Surface plasmon resonance quantification of 13 healing biomarkers indicated differential secretion of most of the quantified factors in culture medium by the multidirectional and unidirectional artificial dermis. Also, there were significant differences between the concentration of some of the factors analyzed in the exudates of wounds grafted with the evaluated artificial dermis. These findings suggest that differential delivery of healing biomarkers induced by the directionality of the scaffold used to produce the multidirectional and unidirectional dermis was sufficient to create two skin wound microenvironments that determined a different outcome of healing. Overall, data indicate that healing of wounds grafted with multidirectional autologous artificial dermis is better than that of the wounds grafted with the unidirectional one.
Bendixsen, C.G.
2017-01-01
Agriculture is the most dangerous occupation in the United States for both workers and bystanders. Family farms highlight an intersection of domesticity and labor. Agrarian ethics of animal husbandry, land stewardship, and kinship are often conflated and constructed to accommodate unpredictable risks (e.g., weather, financial markets). Here, the right or good agricultural practice is assessed in light of an acute event. Risks of illness and injury are often relegated to the realm of acute unpredictability and accepted as intrinsic to desirable ways of life. The following is a description of agrarian ethics and risks generated from personal experience and ethnographic inquiries in the Midwest, the Intermountain West, and Texas over the past 10 years. This paper assesses health and safety within agrarian ethics. These results and discussion lead us to an important conversation about how we can be more detailed in the use of terms like “cultural appropriateness.” It also raises the question as to what is really at stake in public health perspectives like those found in the socioecological and extended parallel process models when deployed in agricultural health and safety. PMID:27749196
Mourad, Elhussein F; Sarhan, Mohamed S; Daanaa, Hassan-Sibroe A; Abdou, Mennatullah; Morsi, Ahmed T; Abdelfadeel, Mohamed R; Elsawey, Hend; Nemr, Rahma; El-Tahan, Mahmoud; Hamza, Mervat A; Abbas, Mohamed; Youssef, Hanan H; Abdelhadi, Abdelhadi A; Amer, Wafaa M; Fayez, Mohamed; Ruppel, Silke; Hegazi, Nabil A
2018-01-01
In order to improve the culturability and biomass production of rhizobacteria, we previously introduced plant-only-based culture media. We herein attempted to widen the scope of plant materials suitable for the preparation of plant-only-based culture media. We chemically analyzed the refuse of turfgrass, cactus, and clover. They were sufficiently rich to support good in vitro growth by rhizobacteria isolates representing Proteobacteria and Firmicutes. They were also adequate and efficient to produce a cell biomass in liquid batch cultures. These culture media were as sufficient as artificial culture media for the cultivation and recovery of the in situ rhizobacteria of barley (Hordeum murinum L.). Based on culture-dependent (CFU plate counting) and culture-independent analyses (qPCR), mowed turfgrass, in particular, supported the highest culturable population of barley endophytes, representing >16% of the total bacterial number quantified with qPCR. This accurately reflected the endophytic community composition, in terms of diversity indices (S′, H′, and D′) based on PCR-DGGE, and clustered the plant culture media together with the qPCR root populations away from the artificial culture media. Despite the promiscuous nature of the plant materials tested to culture the plant microbiome, our results indicated that plant materials of a homologous nature to the tested host plant, at least at the family level, and/or of the same environment were more likely to be selected. Plant-only-based culture media require further refinements in order to provide selectivity for the in vitro growth of members of the plant microbiome, particularly difficult-to-culture bacteria. This will provide insights into their hidden roles in the environment and support future culturomic studies. PMID:29479006
Mourad, Elhussein F; Sarhan, Mohamed S; Daanaa, Hassan-Sibroe A; Abdou, Mennatullah; Morsi, Ahmed T; Abdelfadeel, Mohamed R; Elsawey, Hend; Nemr, Rahma; El-Tahan, Mahmoud; Hamza, Mervat A; Abbas, Mohamed; Youssef, Hanan H; Abdelhadi, Abdelhadi A; Amer, Wafaa M; Fayez, Mohamed; Ruppel, Silke; Hegazi, Nabil A
2018-03-29
In order to improve the culturability and biomass production of rhizobacteria, we previously introduced plant-only-based culture media. We herein attempted to widen the scope of plant materials suitable for the preparation of plant-only-based culture media. We chemically analyzed the refuse of turfgrass, cactus, and clover. They were sufficiently rich to support good in vitro growth by rhizobacteria isolates representing Proteobacteria and Firmicutes. They were also adequate and efficient to produce a cell biomass in liquid batch cultures. These culture media were as sufficient as artificial culture media for the cultivation and recovery of the in situ rhizobacteria of barley (Hordeum murinum L.). Based on culture-dependent (CFU plate counting) and culture-independent analyses (qPCR), mowed turfgrass, in particular, supported the highest culturable population of barley endophytes, representing >16% of the total bacterial number quantified with qPCR. This accurately reflected the endophytic community composition, in terms of diversity indices (S', H', and D') based on PCR-DGGE, and clustered the plant culture media together with the qPCR root populations away from the artificial culture media. Despite the promiscuous nature of the plant materials tested to culture the plant microbiome, our results indicated that plant materials of a homologous nature to the tested host plant, at least at the family level, and/or of the same environment were more likely to be selected. Plant-only-based culture media require further refinements in order to provide selectivity for the in vitro growth of members of the plant microbiome, particularly difficult-to-culture bacteria. This will provide insights into their hidden roles in the environment and support future culturomic studies.
Hu, Congli; Luo, Ying; Wang, Hong; Kuang, Shengnan; Liang, Guojuan; Yang, Yang; Mai, Shaoshan; Yang, Junqing
2017-01-01
The chronic unpredictable mild stress model of depression has been widely used as an experimental tool to investigate human psychopathology. Our objective was to provide an update on the validity and reliability of the chronic unpredictable mild stress model, by analyzing the interrelationships among the indexes using stepwise discriminant analysis and Pearson correlation coefficient to examine the possible combinations. We evaluated the depressive rats in both the presence and the absence of chronic unpredictable mild stress, using weight change, percentage of sucrose preference, coat state, splash test, open-field test, elevated plus-maze test, forced swimming test, and Morris water maze test. The results showed that 6-week-long chronic unpredictable mild stress produces significant depression and anxiety-like behavior. The combination of body weight change, percentage of sucrose preference, coat state score, open-field score, grooming latency of splash test, immobility time in force swimming test, and platform crossing in the Morris water maze test can effectively discriminate between normal and chronic unpredictable mild stress rats. Strong interrelationships were noted among these indexes in both open-field test and elevated plus-maze test. In conclusion, there might be certain criteria for the combination of behavioral endpoints, which is advantageous to more effectively and reliably assess the chronic unpredictable mild stress induced depression model. PMID:28931086
Brüning, Anika; Kloas, Werner; Preuer, Torsten; Hölker, Franz
2018-01-01
Abstract Almost all life on earth has adapted to natural cycles of light and dark by evolving circadian and circannual rhythms to synchronize behavioural and physiological processes with the environment. Artificial light at night (ALAN) is suspected to interfere with these rhythms. In this study we examined the influence of ALAN on nocturnal melatonin and sex steroid blood concentrations and mRNA expression of gonadotropins in the pituitary of European perch (Perca fluviatilis) and roach (Rutilus rutilus). In a rural experimental setting, fish were held in net cages in drainage channels experiencing either additional ALAN of ~15 lx at the water surface or natural light conditions at half-moon. No differences in melatonin concentrations between ALAN and natural conditions were detected. However, blood concentration of sex steroids (17β-estradiol; 11-ketotestosterone) as well as mRNA expression of gonadotropins (luteinizing hormone, follicle stimulating hormone) was reduced in both fish species. We conclude that ALAN can disturb biological rhythms in fish in urban waters. However, impacts on melatonin rhythm might have been blurred by individual differences, sampling methods and moonlight. The effect of ALAN on biomarkers of reproduction suggests a photo-labile period around the onset of gonadogenesis, including the experimental period (August). Light pollution therefore has a great potential to influence crucial life history traits with unpredictable outcome for fish population dynamics. PMID:29686874
Research on evaluating water resource resilience based on projection pursuit classification model
NASA Astrophysics Data System (ADS)
Liu, Dong; Zhao, Dan; Liang, Xu; Wu, Qiuchen
2016-03-01
Water is a fundamental natural resource while agriculture water guarantees the grain output, which shows that the utilization and management of water resource have a significant practical meaning. Regional agricultural water resource system features with unpredictable, self-organization, and non-linear which lays a certain difficulty on the evaluation of regional agriculture water resource resilience. The current research on water resource resilience remains to focus on qualitative analysis and the quantitative analysis is still in the primary stage, thus, according to the above issues, projection pursuit classification model is brought forward. With the help of artificial fish-swarm algorithm (AFSA), it optimizes the projection index function, seeks for the optimal projection direction, and improves AFSA with the application of self-adaptive artificial fish step and crowding factor. Taking Hongxinglong Administration of Heilongjiang as the research base and on the basis of improving AFSA, it established the evaluation of projection pursuit classification model to agriculture water resource system resilience besides the proceeding analysis of projection pursuit classification model on accelerating genetic algorithm. The research shows that the water resource resilience of Hongxinglong is the best than Raohe Farm, and the last 597 Farm. And the further analysis shows that the key driving factors influencing agricultural water resource resilience are precipitation and agriculture water consumption. The research result reveals the restoring situation of the local water resource system, providing foundation for agriculture water resource management.
Brüning, Anika; Kloas, Werner; Preuer, Torsten; Hölker, Franz
2018-01-01
Almost all life on earth has adapted to natural cycles of light and dark by evolving circadian and circannual rhythms to synchronize behavioural and physiological processes with the environment. Artificial light at night (ALAN) is suspected to interfere with these rhythms. In this study we examined the influence of ALAN on nocturnal melatonin and sex steroid blood concentrations and mRNA expression of gonadotropins in the pituitary of European perch ( Perca fluviatilis ) and roach ( Rutilus rutilus ). In a rural experimental setting, fish were held in net cages in drainage channels experiencing either additional ALAN of ~15 lx at the water surface or natural light conditions at half-moon. No differences in melatonin concentrations between ALAN and natural conditions were detected. However, blood concentration of sex steroids (17β-estradiol; 11-ketotestosterone) as well as mRNA expression of gonadotropins (luteinizing hormone, follicle stimulating hormone) was reduced in both fish species. We conclude that ALAN can disturb biological rhythms in fish in urban waters. However, impacts on melatonin rhythm might have been blurred by individual differences, sampling methods and moonlight. The effect of ALAN on biomarkers of reproduction suggests a photo-labile period around the onset of gonadogenesis, including the experimental period (August). Light pollution therefore has a great potential to influence crucial life history traits with unpredictable outcome for fish population dynamics.
Liu, Yang; Lin, Changmin; Zeng, Yang; Li, Haihong; Cai, Bozhi; Huang, Keng; Yuan, Yanping; Li, Yu
2016-01-01
This study aimed to develop and evaluate barium and calcium microcapsules as candidates for scaffolding in artificial dermal papilla. Dermal papilla cells (DPCs) were isolated and cultured by one-step collagenase treatment. The DPC-Ba and DPC-Ca microcapsules were prepared by using a specially designed, high-voltage, electric-field droplet generator. Selected microcapsules were assessed for long-term inductive properties with xenotransplantation into Sprague-Dawley rat ears. Both barium and calcium microcapsules maintained xenogenic dermal papilla cells in an immunoisolated environment and induced the formation of hair follicle structures. Calcium microcapsules showed better biocompatibility, permeability, and cell viability in comparison with barium microcapsules. Before 18 weeks, calcium microcapsules gathered together, with no substantial immune response. After 32 weeks, some microcapsules were near inflammatory cells and wrapped with fiber. A few large hair follicles were found. Control samples showed no marked changes at the implantation site. Barium microcapsules were superior to calcium microcapsules in structural and mechanical stability. The cells encapsulated in hydrogel barium microcapsules exhibited higher short-term viability. This study established a model to culture DPCs in 3D culture conditions. Barium microcapsules may be useful in short-term transplantation study. Calcium microcapsules may provide an effective scaffold for the development of artificial dermal papilla.
Nelson, Brady D; Hajcak, Greg
2017-08-01
Predictability is an important characteristic of threat that impacts defensive motivation and attentional engagement. Supporting research has primarily focused on actual threat (e.g., shocks), and it is unclear whether the predictability of less intense threat (e.g., unpleasant pictures) similarly affects motivation and attention. The present study utilized a within-subject design and examined defensive motivation (startle reflex and self-reported anxiety) and attention (probe N100 and P300) in anticipation of shocks and unpleasant pictures during a no, predictable, and unpredictable threat task. This study also examined the impact of predictability on the P300 to shocks and late positive potential (LPP) to unpleasant pictures. The startle reflex and self-reported anxiety were increased in anticipation of both types of threat relative to no threat. Furthermore, startle potentiation in anticipation of unpredictable threat was greater for shocks compared to unpleasant pictures, but there was no difference for predictable threat. The probe N100 was enhanced in anticipation of unpredictable threat relative to predictable threat and no threat, and the probe P300 was suppressed in anticipation of predictable and unpredictable threat relative to no threat. These effects did not differ between the shock and unpleasant picture trials. Finally, the P300 and early LPP component were increased in response to unpredictable relative to predictable shocks and unpleasant pictures, respectively. The present study suggests that the unpredictability of unpleasant pictures increases defensive motivation, but to a lesser degree relative to actual threat. Moreover, unpredictability enhances attentional engagement in anticipation of, and in reaction to, both types of threat. © 2017 Society for Psychophysiological Research.
Microbial ice nucleators are scavenged from the atmosphere during artificial rain events
NASA Astrophysics Data System (ADS)
Hanlon, Regina; Powers, Craig; Failor, Kevin; Vinatzer, Boris; Schmale, David
2016-04-01
Some microorganisms associated with rain may catalyze the nucleation of ice crystals at significantly warmer temperatures than would normally be required for ice formation, suggesting that they may play an important role in the onset of precipitation. Rain samples collected near the surface of the earth contain an array of microbial ice nucleators, but the little is known about their source(s) and life history. We conducted a series of field experiments to test the hypothesis that microbial ice nucleators are scavenged from the atmosphere by rainfall. Thirty three artificial rain events were conducted over four months (Nov 2014, Dec 2014, April 2015, and June 2015) off the side of the Smart Road Bridge in Blacksburg, VA, USA. In each event, sterile water was dispensed over the side of the bridge and recovered in sterile containers following gravitational settling from the bridge to an open fallow agricultural field below (a distance of ~55m). Microbes scavenged from the artificial rain events were cultured on six different types of agar media (R2A, TSA, CA; +/-cycloheximide), and the ice nucleation activity was examined for colonies cultured from the different media types. Mean CFUs scavenged by artificial rain ranged from 2 to 267 CFUs/mL. Microbial ice nucleators were cultured from 94% (31/33) of the simulated rain events, and represented 1.4% (121/8871) of the total number of colonies assayed. This percentage is similar to the percentage of culturable microbial ice nucleators occurring in about half of the natural rain events studied in Blacksburg, VA. Sequence-assisted identification of the repeatable microbial ice nucleators that were scavenged from the atmosphere showed a number of unique prokaryotic and eukaryotic taxa. This work expands our knowledge of the scavenging properties of rainfall, and suggests that at least some ice nucleators in natural precipitation events may have been scrubbed from the atmosphere during rainfall, and thus are not likely to be involved in the onset of precipitation.
Weiss, S; Henle, P; Roth, W; Bock, R; Boeuf, S; Richter, W
2011-01-01
A computer controlled dynamic bioreactor for continuous ultra-slow uniaxial distraction of a scaffold-free three-dimensional (3D) mesenchymal stem cell pellet culture was designed to investigate the influence of stepless tensile strain on behavior of distinct primary cells like osteoblasts, chondroblasts, or stem cells without the influence of an artificial culture matrix. The main advantages of this device include the following capabilities: (1) Application of uniaxial ultra-slow stepless distraction within a range of 0.5-250 μm/h and real-time control of the distraction distance with high accuracy (mean error -3.4%); (2) tension strain can be applied on a 3D cell culture within a standard CO(2) -incubator without use of an artificial culture matrix; (3) possibility of histological investigation without loss of distraction; (4) feasibility of molecular analysis on RNA and protein level. This is the first report on a distraction device capable of applying continuous tensile strain to a scaffold-free 3D cell culture within physiological ranges of motion comparable to distraction ostegenesis in vivo. We expect the newly designed microdistraction device to increase our understanding on the regulatory mechanisms of mechanical strains on the metabolism of stem cells. Copyright © 2010 American Institute of Chemical Engineers (AIChE).
Computational Modeling of Cultural Dimensions in Adversary Organizations
2010-01-01
Nodes”, In the Proceedings of the 9th Conference on Uncertainty in Artificial Intelli - gence, 1993. [8] Pearl, J. Probabilistic Reasoning in...the artificial life simulations; in con- trast, models with only a few agents typically employ quite sophisticated cognitive agents capa- ble of...Model Construction 45 cisions as to how to allocate scarce ISR assets (two Unmanned Air Systems, UAS ) among the two Red activities while at the same
Implantation of Induced Pluripotent Stem Cell-Derived Tracheal Epithelial Cells.
Ikeda, Masakazu; Imaizumi, Mitsuyoshi; Yoshie, Susumu; Nakamura, Ryosuke; Otsuki, Koshi; Murono, Shigeyuki; Omori, Koichi
2017-07-01
Compared with using autologous tissue, the use of artificial materials in the regeneration of tracheal defects is minimally invasive. However, this technique requires early epithelialization on the inner side of the artificial trachea. After differentiation from induced pluripotent stem cells (iPSCs), tracheal epithelial tissues may be used to produce artificial tracheas. Herein, we aimed to demonstrate that after differentiation from fluorescent protein-labeled iPSCs, tracheal epithelial tissues survived in nude rats with tracheal defects. Red fluorescent tdTomato protein was electroporated into mouse iPSCs to produce tdTomato-labeled iPSCs. Embryoid bodies derived from these iPSCs were then cultured in differentiation medium supplemented with growth factors, followed by culture on air-liquid interfaces for further differentiation into tracheal epithelium. The cells were implanted with artificial tracheas into nude rats with tracheal defects on day 26 of cultivation. On day 7 after implantation, the tracheas were exposed and examined histologically. Tracheal epithelial tissue derived from tdTomato-labeled iPSCs survived in the tracheal defects. Moreover, immunochemical analyses showed that differentiated tissues had epithelial structures similar to those of proximal tracheal tissues. After differentiation from iPSCs, tracheal epithelial tissues survived in rat bodies, warranting the use of iPSCs for epithelial regeneration in tracheal defects.
Unpredictability and the transmission of numbers
NASA Astrophysics Data System (ADS)
Myers, John M.; Madjid, F. Hadi
2016-03-01
Curiously overlooked in physics is its dependence on the transmission of numbers. For example, the transmission of numerical clock readings is implicit in the concept of a coordinate system. The transmission of numbers and other logical distinctions is often achieved over a computer-mediated communications network in the face of an unpredictable environment. By unpredictable we mean something stronger than the spread of probabilities over given possible outcomes, namely an opening to unforeseeable possibilities. Unpredictability, until now overlooked in theoretical physics, makes the transmission of numbers interesting. Based on recent proofs within quantum theory that provide a theoretical foundation to unpredictability, here we show how regularities in physics rest on a background of channels over which numbers are transmitted. As is known to engineers of digital communications, numerical transmissions depend on coordination reminiscent of the cycle of throwing and catching by players tossing a ball back and forth. In digital communications, the players are computers, and the required coordination involves unpredictably adjusting "live clocks" that step these computers through phases of a cycle. We show how this phasing, which we call logical synchronization, constrains number-carrying networks, and, if a spacetime manifold in invoked, put "stripes" on spacetime. Via its logically synchronized channels, a network of live clocks serves as a reference against which to locate events. Such a network in any case underpins a coordinate frame, and in some cases the direct use of a network can be tailored to investigate an unpredictable environment. Examples include explorations of gravitational variations near Earth.
Bio-phobias/techno-philias: virtual reality exposure as treatment for phobias of 'nature'.
Davidson, Joyce; Smith, Mick
2003-09-01
In modern society natural objects like spiders or snakes have a primary role as the loci of specific phobias. Drawing on interviews with members of the UK National Phobics Society (NPS) and associated service providers, this paper explores the implications of the increasingly significant role played by new media, particularly Virtual Reality technologies, in the treatment of these 'bio-phobias'. While advanced technological approaches provide new possibilities for individual sufferers to experiment with and control their phobic responses they also exemplify certain aspects of those specifically modern social relations that are the media within which bio-phobic behaviours develop. From a critical sociological perspective the techno-philic move to the medium of cyber-space may actually exaggerate characteristically modern social relations that seek (but never convincingly manage) to assert complete 'cultural' control over the unpredictable 'natural' elements threatening our cultural integrity.
Preparation and characterization of a novel skin substitute.
Castagnoli, Carlotta; Fumagalli, Mara; Alotto, Daniela; Cambieri, Irene; Casarin, Stefania; Ostorero, Alessia; Casimiri, Raffaella; Germano, Patrizia; Pezzuto, Carla; Stella, Maurizio
2010-01-01
Autologous epidermal cell cultures (CEA) represent a possibility to treat extensive burn lesions, since they allow a significative surface expansion which cannot be achieved with other surgical techniques based on autologous grafting. Moreover currently available CEA preparations are difficult to handle and their take rate is unpredictable. This study aimed at producing and evaluating a new cutaneous biosubstitute made up of alloplastic acellular glycerolized dermis (AAGD) and CEA to overcome these difficulties. A procedure that maintained an intact basement membrane was developed, so as to promote adhesion and growth of CEA on AAGD. Keratinocytes were seeded onto AAGD and cultured up to 21 days. Viability tests and immunohistochemical analysis with specific markers were carried out at 7, 14, and 21 days, to evaluate keratinocyte adhesion, growth, and maturation. Our results support the hypothesis that this newly formed skin substitute could allow its permanent engraftment in clinical application.
ESPEN guideline on ethical aspects of artificial nutrition and hydration.
Druml, Christiane; Ballmer, Peter E; Druml, Wilfred; Oehmichen, Frank; Shenkin, Alan; Singer, Pierre; Soeters, Peter; Weimann, Arved; Bischoff, Stephan C
2016-06-01
The worldwide debate over the use of artificial nutrition and hydration remains controversial although the scientific and medical facts are unequivocal. Artificial nutrition and hydration are a medical intervention, requiring an indication, a therapeutic goal and the will (consent) of the competent patient. The guideline was developed by an international multidisciplinary working group based on the main aspects of the Guideline on "Ethical and Legal Aspects of Artificial Nutrition" published 2013 by the German Society for Nutritional Medicine (DGEM) after conducting a review of specific current literature. The text was extended and introduced a broader view in particular on the impact of culture and religion. The results were discussed at the ESPEN Congress in Lisbon 2015 and accepted in an online survey among ESPEN members. The ESPEN Guideline on Ethical Aspects of Artificial Nutrition and Hydration is focused on the adult patient and provides a critical summary for physicians and caregivers. Special consideration is given to end of life issues and palliative medicine; to dementia and to specific situations like nursing care or the intensive care unit. The respect for autonomy is an important focus of the guideline as well as the careful wording to be used in the communication with patients and families. The other principles of Bioethics like beneficence, non-maleficence and justice are presented in the context of artificial nutrition and hydration. In this respect the withholding and withdrawing of artificial nutrition and/or hydration is discussed. Due to increasingly multicultural societies and the need for awareness of different values and beliefs an elaborated chapter is dedicated to cultural and religious issues and nutrition. Last but not least topics like voluntary refusal of nutrition and fluids, and forced feeding of competent persons (persons on hunger strike) is included in the guideline. Copyright © 2016 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.
Rull, J; Tadeo, E; Lasa, R; Aluja, M
2017-09-19
Dormancy can be defined as a state of suppressed development allowing insects to cope with adverse conditions and plant phenology. Among specialized herbivorous insects exploiting seasonal resources, diapause frequently evolves as a strategy to adjust to predictable plant seasonal cycles. To cope with acyclic and unpredictable climatic events, it has been found for some insects that a proportion of the population undergoes prolonged dormancy. We compared the response of three species in the Rhagoletis cingulata species group exploiting plants differing in fruiting phenology from environments varying in frequency and timing of acyclic climatic catastrophic events (frost during flowering and fruit set) and varying also in the time of the onset of the rainy season. Small proportions (10 months), and large proportions of pupae died without emerging as adults. The number of days elapsed from the end of artificial winter and adult eclosion was longer for R. cingulata exploiting late fruiting Prunus serotina in Northeastern Mexico than for flies recovered from earlier fruiting plants in the central Altiplano. Rhagoletis turpiniae and northeastern R. cingulata pupae suffered high proportions of parasitism. Large proportions of R. cingulata from central Mexico engaging in prolonged dormancy may be explained by the fact that flowering and fruit set for its host, P. serotina var capuli, driven by the timing of maximum precipitation, matches a period of highest probability of frost often resulting in large areas with fruitless trees at unpredictable time intervals. As a consequence of differences in host plant fruiting phenology, central and northeastern Mexican R. cingulata were found to be allochronically isolated. Prolonged dormancy may have resulted in escape from parasitism.
[Unpredicted pregnancy among Chilean young women].
Palma, Irma
2012-03-01
Unpredicted pregnancy is an evolution of the concepts undesired and unplanned pregnancy. It is more common among vulnerable strata of our society and related to lack of education. To explore the prevalence and social concomitants of unpredicted pregnancy among young women. Analysis of the databases of the Sixth National Youth Survey carried out by the Instituto Nacional de la Juventud in Chile during 2009. The universe corresponds to 7570 participants aged between 15 and 29 years, of both genders. Unpredicted pregnancy occurred in 43% of sexually active surveyed women. It was more common among women with a lower educational level and those aged 15 to 24 years, especially during the onset of active sexual life. There was also an inverse relationship between the degree of education, the use of contraception and the age when sexual activity starts. Unpredicted pregnancy is frequent among teenagers and more common among less educated individuals. The frequency of use of contraception is associated in greater measure to the degree of education rather than the age of onset of sexual activity.
The processing of mispredicted and unpredicted sensory inputs interact differently with attention.
Hsu, Yi-Fang; Hämäläinen, Jarmo A; Waszak, Florian
2018-03-01
Prediction and attention are fundamental brain functions in the service of perception. Interestingly, previous investigations found prediction effects independent of attention in some cases but attention-dependent in other cases. The discrepancy might be related to whether the prediction effect was revealed by comparing mispredicted event (where there is incorrect prediction) or unpredicted event (where there is no precise prediction) against predicted event, which are associated with different precision-weighted prediction error. Here we conducted a joint analysis on four published electroencephalography (EEG) datasets which allow for proper dissociation of mispredicted and unpredicted conditions when there was orthogonal manipulation of prediction and attention. We found that the mispredicted-versus-predicted contrast revealed an attention-independent effect of prediction suppression, whereas the unpredicted-versus-predicted contrast revealed a prediction effect that was reversed by attention on auditory N1. The results suggest that mispredicted and unpredicted processing interact with attention in distinct manners. Copyright © 2018 Elsevier Ltd. All rights reserved.
Durai, Mithila; Kobayashi, Kei; Searchfield, Grant D
2018-05-28
To evaluate the feasibility of predictable or unpredictable amplitude-modulated sounds for tinnitus therapy. The study consisted of two parts. (1) An adaptation experiment. Loudness level matches and rating scales (10-point) for loudness and distress were obtained at a silent baseline and at the end of three counterbalanced 30-min exposures (silence, predictable and unpredictable). (2) A qualitative 2-week sound therapy feasibility trial. Participants took home a personal music player (PMP). Part 1: 23 individuals with chronic tinnitus and part 2: seven individuals randomly selected from Part 1. Self-reported tinnitus loudness and annoyance were significantly lower than baseline ratings after acute unpredictable sound exposure. Tinnitus annoyance ratings were also significantly lower than the baseline but the effect was small. The feasibility trial identified that participant preferences for sounds varied. Three participants did not obtain any benefit from either sound. Three participants preferred unpredictable compared to predictable sounds. Some participants had difficulty using the PMP, the average self-report hours of use were low (less <1 h/day). Unpredictable surf-like sounds played using a PMP is a feasible tinnitus treatment. Further work is required to improve the acceptance of the sound and ease of PMP use.
Military Physician and Advanced Practice Nurses’ Knowledge and Use of Modern Natural Family Planning
1996-05-01
NIT* to artificial birth control methods for cultural, personal, religious, or health reasons (Lethbridge, D. J., 1991). A health care provider well...Mormonism, Catholicism, and Orthodox Judaism are specific religious denominations that proscribe artificial means of birth control (Spector, 1991...she value the "natural", for example, and thus reject chemical methods of birth control ? Does she have certain religious beliefs that make some meUiods
Ridley, Christian J A; Day, John G; Smith, Alison G
2018-01-01
Algal-bacterial co-cultures, rather than cultures of algae alone, are regarded as having the potential to enhance productivity and stability in industrial algal cultivation. As with other inocula in biotechnology, to avoid loss of production strains, it is important to develop preservation methods for the long-term storage of these cultures, and one of the most commonly used approaches is cryopreservation. However, whilst there are many reports of cryopreserved xenic algal cultures, little work has been reported on the intentional preservation of both algae and beneficial bacteria in xenic cultures. Instead, studies have focused on the development of methods to conserve the algal strain(s) present, or to avoid overgrowth of bacteria in xenic isolates during the post-thaw recovery phase. Here, we have established a co-cryopreservation method for the long-term storage of both partners in a unialgal-bacterial co-culture. This is an artificial model mutualism between the alga Lobomonas rostrata and the bacterium Mesorhizobium loti , which provides vitamin B 12 (cobalamin) to the alga in return for photosynthate. Using a Planer Kryo 360 controlled-rate cooler, post-thaw viability (PTV) values of 72% were obtained for the co-culture, compared to 91% for the axenic alga. The cultures were successfully revived after 6 months storage in liquid nitrogen, and continued to exhibit mutualism. Furthermore, the alga could be cryopreserved with non-symbiotic bacteria, without bacterial overgrowth occurring. It was also possible to use less controllable passive freezer chambers to cryopreserve the co-cultures, although the PTV was lower. Finally, we demonstrated that an optimised cryopreservation method may be used to prevent the overgrowth potential of non-symbiotic, adventitious bacteria in both axenic and co-cultures of L. rostrata after thawing.
Pupal abnormalities among laboratory-reared gypsy moths
Richard W. Hansen
1991-01-01
Gypsy moth cohorts from 10 near-wild strains (one to six previous generations in culture), six wild strains (field-collected egg masses), and the standard "New Jersey" lab strain (34th and 35th generation in culture) were reared on Otis wheat germ-based artificial diet, in a constant environment. Rearings were begun with newly-hatched first instars; pupae...
Complex Adaptive Systems and the Origins of Adaptive Structure: What Experiments Can Tell Us
ERIC Educational Resources Information Center
Cornish, Hannah; Tamariz, Monica; Kirby, Simon
2009-01-01
Language is a product of both biological and cultural evolution. Clues to the origins of key structural properties of language can be found in the process of cultural transmission between learners. Recent experiments have shown that iterated learning by human participants in the laboratory transforms an initially unstructured artificial language…
A Simple "in Vitro" Culture of Freshwater Prawn Embryos for Laboratory Investigations
ERIC Educational Resources Information Center
Porntrai, Supaporn; Damrongphol, Praneet
2008-01-01
Giant freshwater prawn ("Macrobrachium rosenbergii" De Man) embryos can be cultured "in vitro" to hatching in 15% (v/v) artificial seawater (ASW). This technique can be applied as a bioassay for testing toxicity or for the effects of various substances on embryo development and can be used as a simple and low-cost model for…
Didier, Caroline; Forno, Guillermina; Etcheverrigaray, Marina; Kratje, Ricardo; Goicoechea, Héctor
2009-09-21
The optimal blends of six compounds that should be present in culture media used in recombinant protein production were determined by means of artificial neural networks (ANN) coupled with crossed mixture experimental design. This combination constitutes a novel approach to develop a medium for cultivating genetically engineered mammalian cells. The compounds were collected in two mixtures of three elements each, and the experimental space was determined by a crossed mixture design. Empirical data from 51 experimental units were used in a multiresponse analysis to train artificial neural networks which satisfy different requirements, in order to define two new culture media (Medium 1 and Medium 2) to be used in a continuous biopharmaceutical production process. These media were tested in a bioreactor to produce a recombinant protein in CHO cells. Remarkably, for both predicted media all responses satisfied the predefined goals pursued during the analysis, except in the case of the specific growth rate (mu) observed for Medium 1. ANN analysis proved to be a suitable methodology to be used when dealing with complex experimental designs, as frequently occurs in the optimization of production processes in the biotechnology area. The present work is a new example of the use of ANN for the resolution of a complex, real life system, successfully employed in the context of a biopharmaceutical production process.
Salganik, Matthew J; Watts, Duncan J
2008-01-01
Individuals influence each others' decisions about cultural products such as songs, books, and movies; but to what extent can the perception of success become a "self-fulfilling prophecy"? We have explored this question experimentally by artificially inverting the true popularity of songs in an online "music market," in which 12,207 participants listened to and downloaded songs by unknown bands. We found that most songs experienced self-fulfilling prophecies, in which perceived-but initially false-popularity became real over time. We also found, however, that the inversion was not self-fulfilling for the market as a whole, in part because the very best songs recovered their popularity in the long run. Moreover, the distortion of market information reduced the correlation between appeal and popularity, and led to fewer overall downloads. These results, although partial and speculative, suggest a new approach to the study of cultural markets, and indicate the potential of web-based experiments to explore the social psychological origin of other macro-sociological phenomena.
Rudd, M. Katharine; Mays, Robert W.; Schwartz, Stuart; Willard, Huntington F.
2003-01-01
Human artificial chromosomes have been used to model requirements for human chromosome segregation and to explore the nature of sequences competent for centromere function. Normal human centromeres require specialized chromatin that consists of alpha satellite DNA complexed with epigenetically modified histones and centromere-specific proteins. While several types of alpha satellite DNA have been used to assemble de novo centromeres in artificial chromosome assays, the extent to which they fully recapitulate normal centromere function has not been explored. Here, we have used two kinds of alpha satellite DNA, DXZ1 (from the X chromosome) and D17Z1 (from chromosome 17), to generate human artificial chromosomes. Although artificial chromosomes are mitotically stable over many months in culture, when we examined their segregation in individual cell divisions using an anaphase assay, artificial chromosomes exhibited more segregation errors than natural human chromosomes (P < 0.001). Naturally occurring, but abnormal small ring chromosomes derived from chromosome 17 and the X chromosome also missegregate more than normal chromosomes, implicating overall chromosome size and/or structure in the fidelity of chromosome segregation. As different artificial chromosomes missegregate over a fivefold range, the data suggest that variable centromeric DNA content and/or epigenetic assembly can influence the mitotic behavior of artificial chromosomes. PMID:14560014
Rudd, M Katharine; Mays, Robert W; Schwartz, Stuart; Willard, Huntington F
2003-11-01
Human artificial chromosomes have been used to model requirements for human chromosome segregation and to explore the nature of sequences competent for centromere function. Normal human centromeres require specialized chromatin that consists of alpha satellite DNA complexed with epigenetically modified histones and centromere-specific proteins. While several types of alpha satellite DNA have been used to assemble de novo centromeres in artificial chromosome assays, the extent to which they fully recapitulate normal centromere function has not been explored. Here, we have used two kinds of alpha satellite DNA, DXZ1 (from the X chromosome) and D17Z1 (from chromosome 17), to generate human artificial chromosomes. Although artificial chromosomes are mitotically stable over many months in culture, when we examined their segregation in individual cell divisions using an anaphase assay, artificial chromosomes exhibited more segregation errors than natural human chromosomes (P < 0.001). Naturally occurring, but abnormal small ring chromosomes derived from chromosome 17 and the X chromosome also missegregate more than normal chromosomes, implicating overall chromosome size and/or structure in the fidelity of chromosome segregation. As different artificial chromosomes missegregate over a fivefold range, the data suggest that variable centromeric DNA content and/or epigenetic assembly can influence the mitotic behavior of artificial chromosomes.
The Effects of Prediction on the Perception for Own-Race and Other-Race Faces
Ran, Guangming; Zhang, Qi; Chen, Xu; Pan, Yangu
2014-01-01
Human beings do not passively perceive important social features about others such as race and age in social interactions. Instead, it is proposed that humans might continuously generate predictions about these social features based on prior similar experiences. Pre-awareness of racial information conveyed by others' faces enables individuals to act in “culturally appropriate” ways, which is useful for interpersonal relations in different ethnicity groups. However, little is known about the effects of prediction on the perception for own-race and other-race faces. Here, we addressed this issue using high temporal resolution event-related potential techniques. In total, data from 24 participants (13 women and 11 men) were analyzed. It was found that the N170 amplitudes elicited by other-race faces, but not own-race faces, were significantly smaller in the predictable condition compared to the unpredictable condition, reflecting a switch to holistic processing of other-race faces when those faces were predictable. In this respect, top-down prediction about face race might contribute to the elimination of the other-race effect (one face recognition impairment). Furthermore, smaller P300 amplitudes were observed for the predictable than for unpredictable conditions, which suggested that the prediction of race reduced the neural responses of human brains. PMID:25422892
Disease and thermal acclimation in a more variable and unpredictable climate
NASA Astrophysics Data System (ADS)
Raffel, Thomas R.; Romansic, John M.; Halstead, Neal T.; McMahon, Taegan A.; Venesky, Matthew D.; Rohr, Jason R.
2013-02-01
Global climate change is shifting the distribution of infectious diseases of humans and wildlife with potential adverse consequences for disease control. As well as increasing mean temperatures, climate change is expected to increase climate variability, making climate less predictable. However, few empirical or theoretical studies have considered the effects of climate variability or predictability on disease, despite it being likely that hosts and parasites will have differential responses to climatic shifts. Here we present a theoretical framework for how temperature variation and its predictability influence disease risk by affecting host and parasite acclimation responses. Laboratory experiments conducted in 80 independent incubators, and field data on disease-associated frog declines in Latin America, support the framework and provide evidence that unpredictable temperature fluctuations, on both monthly and diurnal timescales, decrease frog resistance to the pathogenic chytrid fungus Batrachochytrium dendrobatidis. Furthermore, the pattern of temperature-dependent growth of the fungus on frogs was opposite to the pattern of growth in culture, emphasizing the importance of accounting for the host-parasite interaction when predicting climate-dependent disease dynamics. If similar acclimation responses influence other host-parasite systems, as seems likely, then present models, which generally ignore small-scale temporal variability in climate, might provide poor predictions for climate effects on disease.
Pharmacovigilance in Crisis: Drug Safety at a Crossroads.
Price, John
2018-05-01
Pharmacovigilance (PV) is under unprecedented stress from fundamental changes in a booming pharmaceutical industry, from the challenges of creating and maintaining an increasingly complex PV system in a globally diverse regulatory environment, and from unpredicted consequences of historical PV cost-reduction strategies. At the same time, talent availability lags demand, and many PV professionals may no longer be finding personal fulfillment in their careers. The situation creates risks for companies. Advantages and disadvantages of potential strategies to address this increasing problem at a corporate and industry level and in collaboration with regulatory agencies are discussed, as well as opportunities to adopt new technologies, including artificial intelligence and machine-learning to automate pharmacovigilance operations. These approaches would address burdensome and wasteful effort assuring regulatory compliance and free up resources to support the original mission of PV as an important public health activity and to reinvest in the development of new drugs. Copyright © 2018 Elsevier HS Journals, Inc. All rights reserved.
Behavioral similarity measurement based on image processing for robots that use imitative learning
NASA Astrophysics Data System (ADS)
Sterpin B., Dante G.; Martinez S., Fernando; Jacinto G., Edwar
2017-02-01
In the field of the artificial societies, particularly those are based on memetics, imitative behavior is essential for the development of cultural evolution. Applying this concept for robotics, through imitative learning, a robot can acquire behavioral patterns from another robot. Assuming that the learning process must have an instructor and, at least, an apprentice, the fact to obtain a quantitative measurement for their behavioral similarity, would be potentially useful, especially in artificial social systems focused on cultural evolution. In this paper the motor behavior of both kinds of robots, for two simple tasks, is represented by 2D binary images, which are processed in order to measure their behavioral similarity. The results shown here were obtained comparing some similarity measurement methods for binary images.
Rennert, Knut; Nitschke, Mirko; Wallert, Maria; Keune, Natalie; Raasch, Martin; Lorkowski, Stefan; Mosig, Alexander S
2017-01-01
Harvesting cultivated macrophages for tissue engineering purposes by enzymatic digestion of cell adhesion molecules can potentially result in unintended activation, altered function, or behavior of these cells. Thermo-responsive polymer is a promising tool that allows for gentle macrophage detachment without artificial activation prior to subculture within engineered tissue constructs. We therefore characterized different species of thermo-responsive polymers for their suitability as cell substrate and to mediate gentle macrophage detachment by temperature shift. Primary human monocyte- and THP-1-derived macrophages were cultured on thermo-responsive polymers and characterized for phagocytosis and cytokine secretion in response to lipopolysaccharide stimulation. We found that both cell types differentially respond in dependence of culture and stimulation on thermo-responsive polymers. In contrast to THP-1 macrophages, primary monocyte-derived macrophages showed no signs of impaired viability, artificial activation, or altered functionality due to culture on thermo-responsive polymers compared to conventional cell culture. Our study demonstrates that along with commercially available UpCell carriers, two other thermo-responsive polymers based on poly(vinyl methyl ether) blends are attractive candidates for differentiation and gentle detachment of primary monocyte-derived macrophages. In summary, we observed similar functionality and viability of primary monocyte-derived macrophages cultured on thermo-responsive polymers compared to standard cell culture surfaces. While this first generation of custom-made thermo-responsive polymers does not yet outperform standard culture approaches, our results are very promising and provide the basis for exploiting the unique advantages offered by custom-made thermo-responsive polymers to further improve macrophage culture and recovery in the future, including the covalent binding of signaling molecules and the reduction of centrifugation and washing steps. Optimizing these and other benefits of thermo-responsive polymers could greatly improve the culture of macrophages for tissue engineering applications.
Artificial Life Art, Creativity, and Techno-hybridization (editor's introduction).
Dorin, Alan
2015-01-01
Artists and engineers have devised lifelike technology for millennia. Their ingenious devices have often prompted inquiry into our preferences, prejudices, and beliefs about living systems, especially regarding their origins, status, constitution, and behavior. A recurring fabrication technique is shared across artificial life art, science, and engineering. This involves aggregating representations or re-creations of familiar biological parts-techno-hybridization-but the motives of practitioners may differ markedly. This article, and the special issue it introduces, explores how ground familiar to contemporary artificial life science and engineering has been assessed and interpreted in parallel by (a) artists and (b) theorists studying creativity explicitly. This activity offers thoughtful, alternative perspectives on artificial life science and engineering, highlighting and sometimes undermining the fields' underlying assumptions, or exposing avenues that are yet to be explored outside of art. Additionally, art has the potential to engage the general public, supporting and exploring the findings of scientific research and engineering. This adds considerably to the maturity of a culture tackling the issues the discipline of artificial life raises.
Maluach, Alfred M; Misquitta, Keith A; Prevot, Thomas D; Fee, Corey; Sibille, Etienne; Banasr, Mounira; Andreazza, Ana C
2017-01-01
Chronic stress is implicated in the development of various psychiatric illnesses including major depressive disorder. Previous reports suggest that patients with major depressive disorder have increased levels of oxidative stress, including higher levels of DNA/RNA oxidation found in postmortem studies, especially within brain regions responsible for the cognitive and emotional processes disrupted in the disorder. Here, we aimed to investigate whether unpredictable chronic mild stress in mice induces neuronal DNA/RNA oxidation in the prelimbic, infralimbic, and cingulate cortices of the frontal cortex and the basolateral amygdala and to explore potential associations with depressive-like behaviors. We expected that animals subjected to unpredictable chronic mild stress will present higher levels of DNA/RNA oxidation, which will be associated with anxiety-/depressive-like behaviors. C57BL/6J mice were assigned to unpredictable chronic mild stress or nonstress conditions (n = 10/group, 50% females). Following five weeks of unpredictable chronic mild stress exposure, mice were tested in a series of behavioral tests measuring anxiety- and depressive-like behaviors. Frontal cortex and amygdala sections were then immunolabeled for neuronal nuclei, a marker of post-mitotic neurons and anti-8-hydroxy-2-deoxyguanosine/8-oxo-7,8-dihydroguanosine, which reflects both DNA and RNA oxidation. Levels of neuronal DNA/RNA oxidation were increased in the frontal cortex of mice subjected to unpredictable chronic mild stress ( p = 0.0207). Levels of neuronal DNA/RNA oxidation in the frontal cortex were positively correlated with z-emotionality scores for latency to feed in the novelty-suppressed feeding test ( p = 0.0031). Statistically significant differences were not detected in basolateral amygdala levels of neuronal DNA/RNA oxidation between nonstress- and unpredictable chronic mild stress-exposed mice, nor were correlations found with behavioral performances for this region. Our results demonstrate that unpredictable chronic mild stress induces a significant increase in neuronal DNA/RNA oxidation in the frontal cortex that correlate with behavioral readouts of the stress response. A lack of DNA/RNA oxidation alterations in the basolateral amygdala suggests greater vulnerability of frontal cortex neurons to DNA/RNA oxidation in response to unpredictable chronic mild stress. These findings add support to the hypothesis that chronic stress-induced damage to DNA/RNA may be an additional molecular mechanism underlying cellular dysfunctions associated with chronic stress and present in stress-related disorders.
Rossi, Angela; Wistlich, Laura; Heffels, Karl-Heinz; Walles, Heike; Groll, Jürgen
2016-08-01
In addition to dividing tissues into compartments, basement membranes are crucial as cell substrates and to regulate cellular behavior. The development of artificial basement membranes is indispensable for the ultimate formation of functional engineered tissues; however, pose a challenge due to their complex structure. Herein, biodegradable electrospun polyester meshes are presented, exhibiting isotropic or bipolar bioactivation as a biomimetic and biofunctional model of the natural basement membrane. In a one-step preparation process, reactive star-shaped prepolymer additives, which generate a hydrophilic fiber surface, are electrospun with cell-adhesion-mediating peptides, derived from major components of the basement membrane. Human skin cells adhere to the functionalized meshes, and long-term co-culture experiments confirm that the artificial basement membranes recapitulate and preserve tissue specific functions. Several layers of immortalized human keratinocytes grow on the membranes, differentiating toward the surface and expressing typical epithelial markers. Fibroblasts migrate into the reticular lamina mimicking part of the mesh. Both cells types begin to produce extracellular matrix proteins and to remodel the initial membrane. It is shown at the example of skin that the artificial basement membrane design provokes biomimetic responses of different cell types and can thus be used as basis for the future development of basement membrane containing tissues. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Bae, Sang-Woo; Lee, Kang-Woog; Park, Jae-Hyun; Lee, JunHee; Jung, Cho-Rok; Yu, JunJie; Kim, Hwi-Yool; Kim, Dae-Hyun
2018-05-31
Tracheal resection has limited applicability. Although various tracheal replacement strategies were performed using artificial prosthesis, synthetic stents and tissue transplantation, the best method in tracheal reconstruction remains to be identified. Recent advances in tissue engineering enabled 3D bioprinting using various biocompatible materials including living cells, thereby making the product clinically applicable. Moreover, clinical interest in mesenchymal stem cell has dramatically increased. Here, rabbit bone marrow-derived mesenchymal stem cells (bMSC) and rabbit respiratory epithelial cells were cultured. The chondrogenic differentiation level of bMSC cultured in regular media (MSC) and that in chondrogenic media (d-MSC) were compared. Dual cell-containing artificial trachea were manufactured using a 3D bioprinting method with epithelial cells and undifferentiated bMSC (MSC group, n = 6) or with epithelial cells and chondrogenic-differentiated bMSC (d-MSC group, n = 6). d-MSC showed a relatively higher level of glycosaminoglycan (GAG) accumulation and chondrogenic marker gene expression than MSC in vitro. Neo-epithelialization and neo-vascularization were observed in all groups in vivo but neo-cartilage formation was only noted in d-MSC. The epithelial cells in the 3D bioprinted artificial trachea were effective in respiratory epithelium regeneration. Chondrogenic-differentiated bMSC had more neo-cartilage formation potential in a short period. Nevertheless, the cartilage formation was observed only in a localized area.
Takahashi, Maria Beatriz; Leme, Jaci; Caricati, Celso Pereira; Tonso, Aldo; Fernández Núñez, Eutimio Gustavo; Rocha, José Celso
2015-06-01
Currently, mammalian cells are the most utilized hosts for biopharmaceutical production. The culture media for these cell lines include commonly in their composition a pH indicator. Spectroscopic techniques are used for biopharmaceutical process monitoring, among them, UV-Vis spectroscopy has found scarce applications. This work aimed to define artificial neural networks architecture and fit its parameters to predict some nutrients and metabolites, as well as viable cell concentration based on UV-Vis spectral data of mammalian cell bioprocess using phenol red in culture medium. The BHK-21 cell line was used as a mammalian cell model. Off-line spectra of supernatant samples taken from batches performed at different dissolved oxygen concentrations in two bioreactor configurations and with two pH control strategies were used to define two artificial neural networks. According to absolute errors, glutamine (0.13 ± 0.14 mM), glutamate (0.02 ± 0.02 mM), glucose (1.11 ± 1.70 mM), lactate (0.84 ± 0.68 mM) and viable cell concentrations (1.89 10(5) ± 1.90 10(5) cell/mL) were suitably predicted. The prediction error averages for monitored variables were lower than those previously reported using different spectroscopic techniques in combination with partial least squares or artificial neural network. The present work allows for UV-VIS sensor development, and decreases cost related to nutrients and metabolite quantifications.
NASA Astrophysics Data System (ADS)
Madjid, F. Hadi; Myers, John M.
2016-10-01
The world runs on networks over which signals communicate sequences of symbols, e.g. numerals. Examining both engineered and natural communications networks reveals an unsuspected order that depends on contact with an unpredictable entity. This order has three roots. The first is a proof within quantum theory that no evidence can ever determine its explanation, so that an agent choosing an explanation must do so unpredictably. The second root is the showing that clocks that step computers do not "tell time" but serve as self-adjusting symbol-handling agents that regulate "logically synchronized" motion in response to unpredictable disturbances. Such a clock-agent has a certain independence as well as the capacity to communicate via unpredictable symbols with other clock-agents and to adjust its own tick rate in response to that communication. The third root is the noticing of unpredictable symbol exchange in natural systems, including the transmission of symbols found in molecular biology. We introduce a symbol-handling agent as a role played in some cases by a person, for example a physicist who chooses an explanation of given experimental outcomes, and in other cases by some other biological entity, and in still other cases by an inanimate device, such as a computer-based detector used in physical measurements. While we forbear to try to explain the propensity of agents at all levels from cells to civilizations to form and operate networks of logically synchronized symbol-handling agents, we point to this propensity as an overlooked cosmic order, an order structured by the unpredictability ensuing from the proof. Appreciating the cosmic order leads to a conception of agency that replaces volition by unpredictability and reconceives the notion of objectivity in a way that makes a place for agency in the world as described by physics. Some specific implications for physics are outlined.
Bradley, Kevin M; Benner, Steven A
2014-01-01
Synthetic biologists wishing to self-assemble large DNA (L-DNA) constructs from small DNA fragments made by automated synthesis need fragments that hybridize predictably. Such predictability is difficult to obtain with nucleotides built from just the four standard nucleotides. Natural DNA's peculiar combination of strong and weak G:C and A:T pairs, the context-dependence of the strengths of those pairs, unimolecular strand folding that competes with desired interstrand hybridization, and non-Watson-Crick interactions available to standard DNA, all contribute to this unpredictability. In principle, adding extra nucleotides to the genetic alphabet can improve the predictability and reliability of autonomous DNA self-assembly, simply by increasing the information density of oligonucleotide sequences. These extra nucleotides are now available as parts of artificially expanded genetic information systems (AEGIS), and tools are now available to generate entirely standard DNA from AEGIS DNA during PCR amplification. Here, we describe the OligArch (for "oligonucleotide architecting") software, an application that permits synthetic biologists to engineer optimally self-assembling DNA constructs from both six- and eight-letter AEGIS alphabets. This software has been used to design oligonucleotides that self-assemble to form complete genes from 20 or more single-stranded synthetic oligonucleotides. OligArch is therefore a key element of a scalable and integrated infrastructure for the rapid and designed engineering of biology.
Points, Laurie J; Taylor, James Ward; Grizou, Jonathan; Donkers, Kevin; Cronin, Leroy
2018-01-30
Protocell models are used to investigate how cells might have first assembled on Earth. Some, like oil-in-water droplets, can be seemingly simple models, while able to exhibit complex and unpredictable behaviors. How such simple oil-in-water systems can come together to yield complex and life-like behaviors remains a key question. Herein, we illustrate how the combination of automated experimentation and image processing, physicochemical analysis, and machine learning allows significant advances to be made in understanding the driving forces behind oil-in-water droplet behaviors. Utilizing >7,000 experiments collected using an autonomous robotic platform, we illustrate how smart automation cannot only help with exploration, optimization, and discovery of new behaviors, but can also be core to developing fundamental understanding of such systems. Using this process, we were able to relate droplet formulation to behavior via predicted physical properties, and to identify and predict more occurrences of a rare collective droplet behavior, droplet swarming. Proton NMR spectroscopic and qualitative pH methods enabled us to better understand oil dissolution, chemical change, phase transitions, and droplet and aqueous phase flows, illustrating the utility of the combination of smart-automation and traditional analytical chemistry techniques. We further extended our study for the simultaneous exploration of both the oil and aqueous phases using a robotic platform. Overall, this work shows that the combination of chemistry, robotics, and artificial intelligence enables discovery, prediction, and mechanistic understanding in ways that no one approach could achieve alone.
The virulence of multiple Aeromonas spp. were assessed using two models, a neonatal mouse assay and a mouse intestinal cell culture. Transcriptional responses to both infection models were assessed using microarrays. After artificial infection with a variety of Aeromonas spp., ...
Liu, Yung-Chiang; Lee, I-Chi; Lei, Kin Fong
2018-02-14
An in vitro model mimicking the in vivo environment of the brain must be developed to study neural communication and regeneration and to obtain an understanding of cellular and molecular responses. In this work, a multilayered neural network was successfully constructed on a biochip by guiding and promoting neural stem/progenitor cell differentiation and network formation. The biochip consisted of 3 × 3 arrays of cultured wells connected with channels. Neurospheroids were cultured on polyelectrolyte multilayer (PEM) films in the culture wells. Neurite outgrowth and neural differentiation were guided and promoted by the micropatterns and the PEM films. After 5 days in culture, a 3 × 3 neural network was constructed on the biochip. The function and the connections of the network were evaluated by immunocytochemistry and impedance measurements. Neurons were generated and produced functional and recyclable synaptic vesicles. Moreover, the electrical connections of the neural network were confirmed by measuring the impedance across the neurospheroids. The current work facilitates the development of an artificial brain on a chip for investigations of electrical stimulations and recordings of multilayered neural communication and regeneration.
Brazilian and Mexican experiences in the study of incipient domestication.
Lins Neto, Ernani Machado de Freitas; Peroni, Nivaldo; Casas, Alejandro; Parra, Fabiola; Aguirre, Xitlali; Guillén, Susana; Albuquerque, Ulysses Paulino
2014-04-02
Studies of domestication enables a better understanding of human cultures, landscape changes according to peoples' purposes, and evolutionary consequences of human actions on biodiversity. This review aimed at discussing concepts, hypotheses, and current trends in studies of domestication of plants, using examples of cases studied in regions of Mesoamerica and Brazil. We analyzed trends of ethnobiological studies contributing to document processes of domestication and to establish criteria for biodiversity conservation based on traditional ecological knowledge. Based on reviewing our own and other authors' studies we analyzed management patterns and evolutionary trends associated to domestication occurring at plant populations and landscape levels. Particularly, we systematized information documenting: ethnobotanical aspects about plant management and artificial selection mechanisms, morphological consequences of plant management, population genetics of wild and managed plant populations, trends of change in reproduction systems of plants associated to management, and other ecological and physiological aspects influenced by management and domestication. Based on the analysis of study cases of 20 native species of herbs, shrubs and trees we identified similar criteria of artificial selection in different cultural contexts of Mexico and Brazil. Similar evolutionary trends were also identified in morphology (selection in favor of gigantism of useful and correlated parts); organoleptic characteristics such as taste, toxicity, color, texture; reproductive biology, mainly breeding system, phenological changes, and population genetics aspects, maintenance or increasing of genetic diversity in managed populations, high gene flow with wild relatives and low structure maintained by artificial selection. Our review is a first attempt to unify research methods for analyzing a high diversity of processes. Further research should emphasize deeper analyses of contrasting and diverse cultural and ecological contexts for a better understanding of evolution under incipient processes of domestication. Higher research effort is particularly required in Brazil, where studies on this topic are scarcer than in Mexico but where diversity of human cultures managing their also high plant resources diversity offer high potential for documenting the diversity of mechanisms of artificial selection and evolutionary trends. Comparisons and evaluations of incipient domestication in the regions studied as well as the Andean area would significantly contribute to understanding origins and diffusion of the experience of managing and domesticating plants.
Sadoudi, Mohand; Tourdot-Maréchal, Raphaëlle; Rousseaux, Sandrine; Steyer, Damien; Gallardo-Chacón, Joan-Josep; Ballester, Jordi; Vichi, Stefania; Guérin-Schneider, Rémi; Caixach, Josep; Alexandre, Hervé
2012-12-01
There has been increasing interest in the use of selected non-Saccharomyces yeasts in co-culture with Saccharomyces cerevisiae. The main reason is that the multistarter fermentation process is thought to simulate indigenous fermentation, thus increasing wine aroma complexity while avoiding the risks linked to natural fermentation. However, multistarter fermentation is characterised by complex and largely unknown interactions between yeasts. Consequently the resulting wine quality is rather unpredictable. In order to better understand the interactions that take place between non-Saccharomyces and Saccharomyces yeasts during alcoholic fermentation, we analysed the volatile profiles of several mono-culture and co-cultures. Candida zemplinina, Torulaspora delbrueckii and Metschnikowia pulcherrima were used to conduct fermentations either in mono-culture or in co-culture with S. cerevisiae. Up to 48 volatile compounds belonging to different chemical families were quantified. For the first time, we show that C. zemplinina is a strong producer of terpenes and lactones. We demonstrate by means of multivariate analysis that different interactions exist between the co-cultures studied. We observed a synergistic effect on aromatic compound production when M. pulcherrima was in co-culture with S. cerevisiae. However a negative interaction was observed between C. zemplinina and S. cerevisiae, which resulted in a decrease in terpene and lactone content. These interactions are independent of biomass production. The aromatic profiles of T. delbrueckii and S. cerevisiae in mono-culture and in co-culture are very close, and are biomass-dependent, reflecting a neutral interaction. This study reveals that a whole family of compounds could be altered by such interactions. These results suggest that the entire metabolic pathway is affected by these interactions. Copyright © 2012 Elsevier Ltd. All rights reserved.
A tunable artificial circadian clock in clock-defective mice
D'Alessandro, Matthew; Beesley, Stephen; Kim, Jae Kyoung; Chen, Rongmin; Abich, Estela; Cheng, Wayne; Yi, Paul; Takahashi, Joseph S.; Lee, Choogon
2015-01-01
Self-sustaining oscillations are essential for diverse physiological functions such as the cell cycle, insulin secretion and circadian rhythms. Synthetic oscillators using biochemical feedback circuits have been generated in cell culture. These synthetic systems provide important insight into design principles for biological oscillators, but have limited similarity to physiological pathways. Here we report the generation of an artificial, mammalian circadian clock in vivo, capable of generating robust, tunable circadian rhythms. In mice deficient in Per1 and Per2 genes (thus lacking circadian rhythms), we artificially generate PER2 rhythms and restore circadian sleep/wake cycles with an inducible Per2 transgene. Our artificial clock is tunable as the period and phase of the rhythms can be modulated predictably. This feature, and other design principles of our work, might enhance the study and treatment of circadian dysfunction and broader aspects of physiology involving biological oscillators. PMID:26617050
Organotypic slice cultures of human gastric and esophagogastric junction cancer.
Koerfer, Justus; Kallendrusch, Sonja; Merz, Felicitas; Wittekind, Christian; Kubick, Christoph; Kassahun, Woubet T; Schumacher, Guido; Moebius, Christian; Gaßler, Nikolaus; Schopow, Nikolas; Geister, Daniela; Wiechmann, Volker; Weimann, Arved; Eckmann, Christian; Aigner, Achim; Bechmann, Ingo; Lordick, Florian
2016-07-01
Gastric and esophagogastric junction cancers are heterogeneous and aggressive tumors with an unpredictable response to cytotoxic treatment. New methods allowing for the analysis of drug resistance are needed. Here, we describe a novel technique by which human tumor specimens can be cultured ex vivo, preserving parts of the natural cancer microenvironment. Using a tissue chopper, fresh surgical tissue samples were cut in 400 μm slices and cultivated in 6-well plates for up to 6 days. The slices were processed for routine histopathology and immunohistochemistry. Cytokeratin stains (CK8, AE1/3) were applied for determining tumor cellularity, Ki-67 for proliferation, and cleaved caspase-3 staining for apoptosis. The slices were analyzed under naive conditions and following 2-4 days in vitro exposure to 5-FU and cisplatin. The slice culture technology allowed for a good preservation of tissue morphology and tumor cell integrity during the culture period. After chemotherapy exposure, a loss of tumor cellularity and an increase in apoptosis were observed. Drug sensitivity of the tumors could be assessed. Organotypic slice cultures of gastric and esophagogastric junction cancers were successfully established. Cytotoxic drug effects could be monitored. They may be used to examine mechanisms of drug resistance in human tissue and may provide a unique and powerful ex vivo platform for the prediction of treatment response. © 2016 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.
Myxofibrosarcoma primary cultures: molecular and pharmacological profile
De Vita, Alessandro; Recine, Federica; Mercatali, Laura; Miserocchi, Giacomo; Liverani, Chiara; Spadazzi, Chiara; Casadei, Roberto; Bongiovanni, Alberto; Pieri, Federica; Riva, Nada; Amadori, Dino; Ibrahim, Toni
2017-01-01
Background: Myxofibrosarcoma (MFS), formerly considered as a myxoid variant of malignant fibrous histiocytoma, is the most common sarcoma of the extremities in adults and is characterized by a high frequency of local recurrence. The clinical behavior of MFS is unpredictable and the efficacy of chemotherapy is still not well documented. Furthermore, given the relatively recent recognition of MFS as a distinct pathologic entity its cellular and molecular biology has still not been extensively studied in patient-derived preclinical models. We examined the molecular biology and treatment outcomes of high-grade, patient-derived MFS primary cultures. Methods: A total of three patient-derived MFS primary cultures were analyzed. We evaluated the role of CD109 expression and also looked for a correlation between transforming growth factor-beta (TGF-β) expression and sensitivity of the primary cultures to different drugs. Results: CD109 was a promising marker for the identification of more aggressive high-grade MFS and a potential therapeutic target. The results also highlighted the potential role of TGF-β in chemoresistance. Pharmacological analysis confirmed the sensitivity of the cultures to chemotherapy. The most active treatments were epirubicin alone and epirubicin in combination with ifosfamide, the latter representing the current standard of care for soft tissue sarcomas (STSs), including MFS. Conclusions: Our results provide a starting point for further research aimed at improving the management of MFS patients undergoing chemotherapy. PMID:29449896
Suspected seminal vesiculitis in an Asian elephant (Elephas maximus).
Kilburn, Jennifer J; Velguth, Karen E; Backues, Kay A
2011-09-01
A 32-year-old male Asian elephant (Elephas maximus) underwent routine transrectal stimulation for semen collection as part of an artificial insemination program. The procedure consisted of a preinsemination semen collection followed by two consecutive days of semen collections for artificial insemination. The second day's sample contained large numbers of inflammatory cells, intracellular bacteria, and phagocytized sperm. Semen was submitted for culture and sensitivity. Culture revealed Acinetobacter lwoffii, Staphylococcus intermedius, Kocuria roseus, and an unidentified gram-positive organism. Empirical antibiotic therapy with trimethoprim sulfa was initiated and then changed to enrofloxacin based on sensitivity panel results for a total of 28 days of treatment. Diagnostic semen collections were performed during treatment and 2 wk posttreatment to determine the success of therapy. Posttreatment collections revealed resolution of the inflammation. The origin of the infection was suspected to be the seminal vesicles.
Bielská, Lucie; Hovorková, Ivana; Kuta, Jan; Machát, Jiří; Hofman, Jakub
2017-01-01
Artificial soil (AS) is used in soil ecotoxicology as a test medium or reference matrix. AS is prepared according to standard OECD/ISO protocols and components of local sources are usually used by laboratories. This may result in significant inter-laboratory variations in AS properties and, consequently, in the fate and bioavailability of tested chemicals. In order to reveal the extent and sources of variations, the batch equilibrium method was applied to measure the sorption of 2 model compounds (phenanthrene and cadmium) to 21 artificial soils from different laboratories. The distribution coefficients (K d ) of phenanthrene and cadmium varied over one order of magnitude: from 5.3 to 61.5L/kg for phenanthrene and from 17.9 to 190L/kg for cadmium. Variations in phenanthrene sorption could not be reliably explained by measured soil properties; not even by the total organic carbon (TOC) content which was expected. Cadmium logK d values significantly correlated with cation exchange capacity (CEC), pH H2O and pH KCl , with Pearson correlation coefficients of 0.62, 0.80, and 0.79, respectively. CEC and pH H2O together were able to explain 72% of cadmium logK d variability in the following model: logK d =0.29pH H2O +0.0032 CEC -0.53. Similarly, 66% of cadmium logK d variability could be explained by CEC and pH KCl in the model: logKd=0.27pH KCl +0.0028 CEC -0.23. Variable cadmium sorption in differing ASs could be partially treated with these models. However, considering the unpredictable variability of phenanthrene sorption, a more reliable solution for reducing the variability of ASs from different laboratories would be better harmonization of AS preparation and composition. Copyright © 2016 Elsevier Inc. All rights reserved.
Hsieh, Teng-Fu; Chen, Chi-Cheng; Chang, Chao-Hsiang; Yu, Ai-Lin; Ma, Wen-Lung; Shyr, Chih-Rong
2013-07-01
Upper urinary tract urothelial cell carcinoma (UUT-UCC) is a rare yet aggressive urologic tumor with a high rate of recurrence and metastasis, resulting in high mortality. Chemotherapy has been used to prevent recurrence and treat metastatic UUT-UCCs. Although UUT-UCC is sensitive to chemotherapy, the patients' responses to therapy vary and the therapy outcome is unpredictable. Therefore, the identification of patients who are at high risk of failure in chemotherapy is important for accurate prognostication, patient counseling, and better therapy. We have obtained cells from UUT-UCC tumor tissues after surgery and established individual primary cultured cell lines, which were used to evaluate E-cadherin and Ki-67 proliferation marker expression and their chemosensitivity to chemotherapeutic drugs. Differential Ki-67 expression and chemosensitivity were observed in these primary cultured cell lines, suggesting these types of UUT-UCC cell lines could provide a platform for determining prognostic makers and evaluating the efficacy of chemotherapy. In conclusion, primary cultured cell lines from individual patients will be a great tool for evaluating and determining each individual's personalized chemotherapy course and for testing and screening new chemotherapeutic agents against UUT-UCCs. Copyright © 2012 Elsevier GmbH. All rights reserved.
Underprotection of unpredictable statistical lives compared to predictable ones
Evans, Nicholas G.; Cotton-Barratt, Owen
2016-01-01
Existing ethical discussion considers the differences in care for identified versus statistical lives. However there has been little attention to the different degrees of care that are taken for different kinds of statistical lives. Here we argue that for a given number of statistical lives at stake, there will sometimes be different, and usually greater care taken to protect predictable statistical lives, in which the number of lives that will be lost can be predicted fairly accurately, than for unpredictable statistical lives, where the lives are at stake because of a low-probability event, such that most likely no one will be affected by the decision but with low probability some lives will be at stake. One reason for this difference is the statistical challenge of estimating low probabilities, and in particular the tendency of common approaches to underestimate these probabilities. Another is the existence of rational incentives to treat unpredictable risks as if the probabilities were lower than they are. Some of these factors apply outside the pure economic context, to institutions, individuals, and governments. We argue that there is no ethical reason to treat unpredictable statistical lives differently from predictable statistical lives. Moreover, lives that are unpredictable from the perspective of an individual agent may become predictable when aggregated to the level of a societal decision. Underprotection of unpredictable statistical lives is a form of market failure that may need to be corrected by altering regulation, introducing compulsory liability insurance, or other social policies. PMID:27393181
Evolutionary Intelligence and Communication in Societies of Virtually Embodied Agents
NASA Astrophysics Data System (ADS)
Nguyen, Binh; Skabar, Andrew
In order to overcome the knowledge bottleneck problem, AI researchers have attempted to develop systems that are capable of automated knowledge acquisition. However, learning in these systems is hindered by context (i.e., symbol-grounding) problems, which are caused by the systems lacking the unifying structure of bodies, situations and needs that typify human learning. While the fields of Embodied Artificial Intelligence and Artificial Life have come a long way towards demonstrating how artificial systems can develop knowledge of the physical and social worlds, the focus in these areas has been on low level intelligence, and it is not clear how, such systems can be extended to deal with higher-level knowledge. In this paper, we argue that we can build towards a higher level intelligence by framing the problem as one of stimulating the development of culture and language. Specifically, we identify three important limitations that face the development of culture and language in AI systems, and propose how these limitations can be overcome. We will do this through borrowing ideas from the evolutionary sciences, which have explored how interactions between embodiment and environment have shaped the development of human intelligence and knowledge.
Tummon, I S; Dudley, D K; Walters, J H
1981-07-01
Genital herpes is a sexually transmitted disease caused by the herpes simplex virus. Following the initial infection the virus becomes latent in the sacral ganglia. Approximately 80% of patients are then subject to milder but unpredictable recurrences and may shed the virus even when they are asymptomatic. The disorder causes concern because genital herpes in the mother can result in rare but catastrophic neonatal infection and because of a possible association between genital herpes and cancer of the cervix. No effective treatment is as yet available. Weekly monitoring for virus by cervical culture from 32 weeks' gestation is recommended for women with a history of genital herpes and for those whose sexual partner has such a history.
Ryan, Charlotte; Anastario, Mike; DaCunha, Alfredo
2006-02-01
Stressing relation-building and participatory communication approaches, the Rhode Island Coalition against Domestic Violence worked with journalists to develop a best practices handbook on news coverage of domestic violence murders. This study compares print coverage of domestic violence murders prehandbook (1996-1999) and posthandbook (2000-2002). Significant changes include increased labeling of the murder of intimates as domestic violence and doubled usage of advocates as sources. As a result, domestic violence murders, previously framed as unpredictable private tragedies, are more commonly framed posthandbook as social problems warranting public intervention. The authors conclude that relation-building approaches can affect news cultures and public discourse when conducted in conjunction with comprehensive participatory communications strategies.
Grillon, Christian; O'Connell, Katherine; Lieberman, Lynne; Alvarez, Gabriella; Geraci, Marilla; Pine, Daniel S; Ernst, Monique
2017-10-01
Delineating specific clinical phenotypes of anxiety disorders is a crucial step toward better classification and understanding of these conditions. The present study sought to identify differential aversive responses to predictable and unpredictable threat of shock in healthy comparisons and in non-medicated anxiety patients with and without a history of panic attacks (PAs). 143 adults (72 healthy controls; 71 patients with generalized anxiety disorder (GAD) or/and social anxiety disorder (SAD), 24 with and 47 without PAs) were exposed to three conditions: 1) predictable shocks signaled by a cue, 2) unpredictable shocks, and 3) no shock. Startle magnitude was used to assess aversive responses. Across disorders, a PA history was specifically associated with hypersensitivity to unpredictable threat. By disorder, SAD was associated with hypersensitivity to predictable threat, whereas GAD was associated with exaggerated baseline startle. These results identified three physiological patterns. The first is hypersensitivity to unpredictable threat in individuals with PAs. The second is hypersensitivity to predictable threat, which characterizes SAD. The third is enhanced baseline startle in GAD, which may reflect propensity for self-generated anxious thoughts in the absence of imminent danger. These results inform current thinking by linking specific clinical features to particular physiology profiles.
A negative ion beam application to artificial formation of neuron network in culture
NASA Astrophysics Data System (ADS)
Tsuji, Hiroshi; Sato, Hiroko; Baba, Takahiro; Gotoh, Yasuhito; Ishikawa, Junzo
2000-02-01
A negative ion beam modification of the biocompatibility of polystyrene surface was investigated for the artificial formation of neuron network in culture with respect to negative ion species. Negative ions of silver, copper or carbon were implanted in nontreated polystyrene (NTPS) dishes at conditions of 20 keV and 3×1015ions/cm2 through a mask with many slits of 60 μm in width. For the surface wettability, the contact angle of ion-implanted NTPS was about 75° for silver-negative ions, which was lower than 86° of the original NTPS. For carbon implantation, on the contrary, the contact angles did not change from the original value. In culture experiment using neuron cells of PC-12h (rat adrenal pheochromocytoma), the cells cultured with serum medium in two days showed the cell attachment and growth in number only at the ion-implanted region on NTPS for all ion species. In another two days in culture with nonserum medium including a nerve growth factor, the outgrowth of neural protrusions was also observed only at the ion-implanted region for all ion species. There was a difference in number of attached cells for ion species. The silver-negative ion-implanted NTPS had a large effect for cell attachment compared with other two ion species. This reason is considered to be due to the lowest contract angles among them.
Bolshevik disease and Stalinist terror: on the historical casuistry of artificial pneumothorax.
Polianski, Igor J
2015-01-01
From its initial development by Carlo Forlanini at the end of the nineteenth century until the advent of antibiotics in the 1940s, artificial pneumothorax was one of the most widely used treatments for pulmonary tuberculosis. However, there were strongly held reservations about this therapy because of its risks and side effects. In the Soviet Union under Stalin, such uncertainties became instruments of political denunciation. The leading Soviet pulmonary physician Volf S. Kholtsman (1886-1941) was alleged to have used the so-called 'aristocratic therapy' of artificial pneumothorax to kill prominent Bolsheviks. Drawing on documents from Stalin's personal Secretariat, this historical study of the pneumothorax scandal contributes to the cultural history of tuberculosis, showing how it was instrumentalised for political purposes.
Perin, Giorgio; Bellan, Alessandra; Segalla, Anna; Meneghesso, Andrea; Alboresi, Alessandro; Morosinotto, Tomas
2015-01-01
The productivity of an algal culture depends on how efficiently it converts sunlight into biomass and lipids. Wild-type algae in their natural environment evolved to compete for light energy and maximize individual cell growth; however, in a photobioreactor, global productivity should be maximized. Improving light use efficiency is one of the primary aims of algae biotechnological research, and genetic engineering can play a major role in attaining this goal. In this work, we generated a collection of Nannochloropsis gaditana mutant strains and screened them for alterations in the photosynthetic apparatus. The selected mutant strains exhibited diverse phenotypes, some of which are potentially beneficial under the specific artificial conditions of a photobioreactor. Particular attention was given to strains showing reduced cellular pigment contents, and further characterization revealed that some of the selected strains exhibited improved photosynthetic activity; in at least one case, this trait corresponded to improved biomass productivity in lab-scale cultures. This work demonstrates that genetic modification of N. gaditana has the potential to generate strains with improved biomass productivity when cultivated under the artificial conditions of a photobioreactor.
Salganik, Matthew J.; Watts, Duncan J.
2013-01-01
Individuals influence each others’ decisions about cultural products such as songs, books, and movies; but to what extent can the perception of success become a “self-fulfilling prophecy”? We have explored this question experimentally by artificially inverting the true popularity of songs in an online “music market,” in which 12,207 participants listened to and downloaded songs by unknown bands. We found that most songs experienced self-fulfilling prophecies, in which perceived—but initially false—popularity became real over time. We also found, however, that the inversion was not self-fulfilling for the market as a whole, in part because the very best songs recovered their popularity in the long run. Moreover, the distortion of market information reduced the correlation between appeal and popularity, and led to fewer overall downloads. These results, although partial and speculative, suggest a new approach to the study of cultural markets, and indicate the potential of web-based experiments to explore the social psychological origin of other macro-sociological phenomena. PMID:24078078
Hammond, Elizabeth R; McGillivray, Brent C; Wicker, Sophie M; Peek, John C; Shelling, Andrew N; Stone, Peter; Chamley, Larry W; Cree, Lynsey M
2017-01-01
To characterize nuclear and mitochondrial DNA (mtDNA) in spent culture media from normally developing blastocysts to determine whether it could be used for noninvasive genetic assessment. Prospective embryo cohort study. Academic center and private in vitro fertilization (IVF) clinic. Seventy patients undergoing intracytoplasmic sperm injection (ICSI) and 227 blastocysts. Culture media assessment, artificial blastocoele fluid collapse and DNA analysis using digital polymerase chain reaction (dPCR), long-range PCR, quantitative PCR (qPCR), and DNA fingerprinting. Presence of nuclear and mtDNA in three different commercial culture media from Vitrolife and Irvine Scientific, spent embryo media assessment at the cleavage and blastocyst stages of development, and analysis of the internal media controls for each patient that had been exposed to identical conditions as embryo media but did not come into contact with embryos. Higher levels of nuclear and mtDNA were observed in the culture media that had been exposed to embryos compared with the internal media controls. Nuclear DNA (∼4 copies) and mtDNA (∼600 copies) could be detected in spent media, and the levels increased at the blastocyst stage. No increase in DNA was detected after artificial blastocoele fluid collapse. Mixed sex chromosome DNA was detected. This originated from contamination in the culture media and from maternal (cumulus) cells. Due to the limited amount of template, the presence of embryonic nuclear DNA could not be confirmed by DNA fingerprinting analysis. Currently DNA from culture media cannot be used for genetic assessment because embryo-associated structures release DNA into the culture medium and the DNA is of mixed origin. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Scavenging of ice-nucleating microorganisms from the atmosphere by artificial rain events
NASA Astrophysics Data System (ADS)
Hanlon, Regina; Powers, Craig; Failor, Kevin; Vinatzer, Boris; Schmale, David
2015-04-01
Little is known about how microorganisms are scavenged from the atmosphere during rainfall. Microorganisms are abundant and diverse in rain (precipitation) collected near the surface of the earth. Some of these rain-associated microorganisms produce proteins that catalyze the nucleation of ice crystals at significantly warmer temperatures than would normally be required for ice formation, suggesting that they may play important roles in weather, including the onset of precipitation. We conducted a series of field experiments to test the hypothesis that ice-nucleating microorganisms are scavenged from the atmosphere by rainfall. Thirteen artificial rain events were conducted off the side of the Smart Road Bridge in Blacksburg, VA, USA. In each event, sterile water was dispensed over the side of the bridge (simulated rainfall), and recovered in sterile containers following gravitational settling from the side of the bridge to an open fallow agricultural field below (a distance of ~55m from the release site to the collection site). Microbes scavenged from the artificial rain events were cultured on six different types of agar media (R2A, TSA, CA; +/- cycloheximide) and the ice nucleation activity was examined for colonies cultured from the different media types. Mean CFUs scavenged by artificial rain ranged from 83 to 196 CFUs/mL across all six media types. Ice-nucleating microorganisms were recovered from 85% (11/13) of the simulated rain events, and represented about 1% of the total number of colonies assayed from each event. Strikingly, this percentage is nearly identical to the percentage of culturable ice-nucleating microorganisms occurring in about half of the natural rain events studied to date in Blacksburg, Virginia. This work expands our knowledge of the scavenging properties of rain, and suggests that at least some ice nucleators in natural precipitation events may have been stripped from the atmosphere during rainfall, thus negating their potential role in the onset of precipitation.
Alcohol Control in Cuba: Preventing Countervailing Cultural and Mass Media Influences.
González-Menéndez, Ricardo Á
2016-07-01
Harmful use of alcohol-the prime gateway drug to other addictions-is also a problem in Cuba, even though the National Program for Prevention of Harmful Use of Alcohol includes the most effective measures used in analogous programs around the world. As a participant in the program's committee and empirical observer of its accomplishments and unaccomplished goals, I draw attention to the community's attitude of tolerance toward intoxication manifested by the lack of proportional consequences, and I insist on the need to broaden the community's understanding of the risks of non-social drinking, which in Latin America is practically limited to alcoholism and its complications. This undervalues the damage wreaked by unpredictable and dangerous behavior under the influence, as well as the suffering of codependents and other "passive drinkers," and the adverse effects of even social drinking. KEYWORDS Alcohol abuse/prevention and control, alcohol consumption, alcohol drinking/culture, alcoholism, drinking behavior, behavior and behavior mechanisms, social determinants of health, social reinforcement, mass media, communication, Cuba.
NASA Astrophysics Data System (ADS)
Sherwin, Evan D.; Henrion, Max; Azevedo, Inês M. L.
2018-04-01
Long-term projections of energy consumption, supply and prices heavily influence decisions regarding long-lived energy infrastructure. Predicting the evolution of these quantities over multiple years to decades is a difficult task. Here, we estimate year-on-year volatility and unpredictability over multi-decade time frames for many quantities in the US energy system using historical projections. We determine the distribution over time of the most extreme projection errors (unpredictability) from 1985 to 2014, and the largest year-over-year changes (volatility) in the quantities themselves from 1949 to 2014. Our results show that both volatility and unpredictability have increased in the past decade, compared to the three and two decades before it. These findings may be useful for energy decision-makers to consider as they invest in and regulate long-lived energy infrastructure in a deeply uncertain world.
On the use of the T-REx tetracycline-inducible gene expression system in vivo.
Dobrovolsky, Vasily N; Heflich, Robert H
2007-10-15
Components of the commercially available T-REx system were used to create two types of transgenic mice. The first contained the tetracycline-repressor transgene under the control of the CMV promoter/enhancer; the second type contained a green fluorescent protein (GFP) reporter transgene under the control of the CMV promoter/enhancer with a tetracycline repressor operator sequence. Transgene expression was unpredictable in animals containing the individual transgenes. Animals with the reporter transgene expressed GFP in only some tissues (e.g., pancreas, kidney), and one line of reporter transgenic animals developed kidney disease, presumably due to expression of the transgene. The two types of transgenic animals were crossbred to produce double-transgenic animals with the object of regulating the expression of the reporter in vivo. When a similar double-transgenic system was constructed in cultured cells, the repressor protein suppressed the transcription of the reporter transgene. The presence of the repressor in double-transgenic animals had no effect on the expression of the reporter; double transgenic animals developed the same kidney disease that was seen in singly transgenic mice with the reporter. Our results indicate that transgenes under the control of the CMV promoter in the T-REx system express somewhat unpredictably and in only a limited number of tissues, making the use of this system for the development of in vivo models problematical. Copyright 2007 Wiley Periodicals, Inc.
Yoshioka, Kumiko; Reavley, Nicola J; MacKinnon, Andrew J; Jorm, Anthony F
2014-01-30
The aim of the current study was to assess the stigmatising attitudes of Japanese high school students towards people with depression, social phobia and psychosis/schizophrenia. In 2011, 311 students aged 15-18 years filled out an anonymous self-report questionnaire, which included a case vignette describing either depression, schizophrenia or social phobia and two questionnaires to assess stigmatising attitudes towards people with these disorders. Exploratory Structural Equation Modelling (ESEM) was used to determine the dimensionality and loading pattern of the stigma items in the two scales, to establish dimensions of stigma and to compare levels on these dimensions between genders. Stigmatising attitudes towards people with mental disorders in young Japanese people are substantial. ESEM revealed that the structure of stigmatising attitudes in young Japanese people is comparable in personal and perceived attitude stigma, with each forming distinct dimensions and each comprising 'weak not sick' and 'dangerous/unpredictable' components. The social distance dimension of stigma was separate from other components. Stigmatising attitudes relating to dangerousness/unpredictability were the lowest for social phobia and highest for schizophrenia. Females had lower stigmatising attitudes than males. These findings echo those of Australian studies and extend them by demonstrating a similar structure of stigma in another cultural group, namely young Japanese people. Crown Copyright © 2013 Published by Elsevier Ireland Ltd All rights reserved.
Kaye, Jesse T.; Bradford, Daniel E.; Magruder, Katherine P.; Curtin, John J.
2017-01-01
Stressors clearly contribute to addiction etiology and relapse in humans, but our understanding of specific mechanisms remains limited. Rodent models of addiction offer the power, flexibility, and precision necessary to delineate the causal role and specific mechanisms through which stressors influence alcohol and other drug use. This review describes a program of research using startle potentiation to unpredictable stressors that is well positioned to translate between animal models and clinical research with humans on stress neuroadaptations in addiction. This research rests on a solid foundation provided by three separate pillars of evidence from (a) rodent behavioral neuroscience on stress neuroadaptations in addiction, (b) rodent affective neuroscience on startle potentiation, and (c) human addiction and affective science with startle potentiation. Rodent stress neuroadaptation models implicate adaptations in corticotropin-releasing factor and norepinephrine circuits within the central extended amygdala following chronic alcohol and other drug use that mediate anxious behaviors and stress-induced reinstatement among drug-dependent rodents. Basic affective neuroscience indicates that these same neural mechanisms are involved in startle potentiation to unpredictable stressors in particular (vs. predictable stressors). We believe that synthesis of these evidence bases should focus us on the role of unpredictable stressors in addiction etiology and relapse. Startle potentiation in unpredictable stressor tasks is proposed to provide an attractive and flexible test bed to encourage tight translation and reverse translation between animal models and human clinical research on stress neuroadaptations. Experimental therapeutics approaches focused on unpredictable stressors hold high promise to identify, repurpose, or refine pharmacological and psychosocial interventions for addiction. PMID:28499100
Kaye, Jesse T; Bradford, Daniel E; Magruder, Katherine P; Curtin, John J
2017-05-01
Stressors clearly contribute to addiction etiology and relapse in humans, but our understanding of specific mechanisms remains limited. Rodent models of addiction offer the power, flexibility, and precision necessary to delineate the causal role and specific mechanisms through which stressors influence alcohol and other drug use. This review describes a program of research using startle potentiation to unpredictable stressors that is well positioned to translate between animal models and clinical research with humans on stress neuroadaptations in addiction. This research rests on a solid foundation provided by three separate pillars of evidence from (a) rodent behavioral neuroscience on stress neuroadaptations in addiction, (b) rodent affective neuroscience on startle potentiation, and (c) human addiction and affective science with startle potentiation. Rodent stress neuroadaptation models implicate adaptations in corticotropin-releasing factor and norepinephrine circuits within the central extended amygdala following chronic alcohol and other drug use that mediate anxious behaviors and stress-induced reinstatement among drug-dependent rodents. Basic affective neuroscience indicates that these same neural mechanisms are involved in startle potentiation to unpredictable stressors in particular (vs. predictable stressors). We believe that synthesis of these evidence bases should focus us on the role of unpredictable stressors in addiction etiology and relapse. Startle potentiation in unpredictable stressor tasks is proposed to provide an attractive and flexible test bed to encourage tight translation and reverse translation between animal models and human clinical research on stress neuroadaptations. Experimental therapeutics approaches focused on unpredictable stressors hold high promise to identify, repurpose, or refine pharmacological and psychosocial interventions for addiction.
Interlingua: An Interlanguage.
ERIC Educational Resources Information Center
Tinsley, Royal L., Jr.
This paper presents the historical background and practical applications of "Interlingua," a language system of common words derived from four control languages. Interlingua and "Esperanto," another artificial language, are compared, emphasizing that international, cross-cultural communication is best served, not by the…
Correlation between plasma component levels of cultured fish and resistance to bacterial infection
Maita, M.; Satoh, K.-I.; Fukuda, Y.; Lee, H.-K.; Winton, J.R.; Okamoto, N.
1998-01-01
Mortalities of yellowtail Seriola quinqueradiata artificially infected with Lactococcus garvieae and of rainbow trout Oncorhynchus mykiss artificially infected with Vibrio anguillarum were compared with the levels of plasma components measured prior to challenge. The levels of plasma total cholesterol, free cholesterol and phospholipid of fish surviving infection were significantly higher in both yellowtail and rainbow trout than those of fish which died during the challenge test. Mortality of yellowtail with plasma total cholesterol levels lower than 250 mg/100 ml was significantly higher than that of fish which had cholesterol levels higher than 275 mg/100 ml (p < 0.05). Rainbow trout whose cholesterol was lower than 520 mg/100 ml suffered a significantly higher mortality due to vibriosis than fish having cholesterol levels higher than 560 mg/100 ml (p < 0.005). These results indicate that low levels of plasma lipid components may be an indicator of lowered disease resistance in cultured fish.
Overview of biology and aquaculture of Amur sturgeon (Acipenser schrenckii) in China
Zhuang, P.; Kynard, B.; Zhang, L.; Zhang, T.; Zhang, Z.; Li, D.
2002-01-01
Amur sturgeon, Acipenser schrenckii is a large riverine species (max. 3 m length and 190 kg weight) native to the Amur River. In the middle Amur River, males first spawn at 7-8 years of age and females at 9-10 years. Due to overfishing and habitat alteration, the abundance of wild stocks has rapidly declined in recent years. Using wild adults, artificial spawning began in the 1950s in China, and since the early 1990s Amur sturgeon has become the most popular sturgeon for aquaculture. The species is adaptive to many conditions of artificial culture, including traditional Chinese fish culture ponds, lakes, reservoirs, and cages. It will grow well on many types of food, and 1-year-old fish reared on commercial diets weigh 900-1200 g. Based on the examination of females reared for broodstock, first full sexual maturity is expected at 5-6 years of age.
The culture contributing to interruptions in the nursing work environment: An ethnography.
Hopkinson, Susan G; Wiegand, Debra L
2017-12-01
To understand the occurrence of interruptions within the culture of the medical nursing unit work environment. Interruptions may lead to errors in nursing work. Little is known about how the culture of the nursing work environment contributes to interruptions. A micro-focused ethnographic study was conducted. Data collection involved extensive observation of a nursing unit, 1:1 observations of nurses and follow-up interviews with the nurses. Data were analysed from unstructured field notes and interview transcripts. The definitions of interruption and culture guided coding, categorising and identification of themes. A framework was developed that describes the medical nursing unit as a complex culture full of unpredictable, nonlinear changes that affect the entire interconnected system, often in the form of an interruption. The cultural elements contributing to interruptions included (i) the value placed on excellence in patient care and meeting personal needs, (ii) the beliefs that the nurses had to do everything by themselves and that every phone call was important, (iii) the patterns of changing patients, patient transport and coordination of resources and (iv) the normative practices of communicating and adapting. Interruptions are an integral part of the culture of a medical nursing unit. Uniformly decreasing interruptions may disrupt current practices, such as communication to coordinate care, that are central to nursing work. In future research, the nursing work environment must be looked at through the lens of a complex system. Interventions to minimise the negative impact of interruptions must take into account the culture of the nursing as a complex adaptive system. Nurses should be educated on their own contribution to interruptions and issues addressed at a system level, rather than isolating the interruption as the central issue. © 2017 John Wiley & Sons Ltd.
Cultivation of Marine Sponges.
Osinga; Tramper; Wijffels
1999-11-01
There is increasing interest in biotechnological production of marine sponge biomass owing to the discovery of many commercially important secondary metabolites in this group of animals. In this article, different approaches to producing sponge biomass are reviewed, and several factors that possibly influence culture success are evaluated. In situ sponge aquacultures, based on old methods for producing commercial bath sponges, are still the easiest and least expensive way to obtain sponge biomass in bulk. However, success of cultivation with this method strongly depends on the unpredictable and often suboptimal natural environment. Hence, a better-defined production system would be desirable. Some progress has been made with culturing sponges in semicontrolled systems, but these still use unfiltered natural seawater. Cultivation of sponges under completely controlled conditions has remained a problem. When designing an in vitro cultivation method, it is important to determine both qualitatively and quantitatively the nutritional demands of the species that is to be cultured. An adequate supply of food seems to be the key to successful sponge culture. Recently, some progress has been made with sponge cell cultures. The advantage of cell cultures is that they are completely controlled and can easily be manipulated for optimal production of the target metabolites. However, this technique is still in its infancy: a continuous cell line has yet to be established. Axenic cultures of sponge aggregates (primmorphs) may provide an alternative to cell culture. Some sponge metabolites are, in fact, produced by endosymbiotic bacteria or algae that live in the sponge tissue. Only a few of these endosymbionts have been cultivated so far. The biotechnology for the production of sponge metabolites needs further development. Research efforts should be continued to enable commercial exploitation of this valuable natural resource in the near future.
An artificial diet containing plant pollen for the mealybug predator Cryptolaemus montrouzieri.
Xie, Jiaqin; Wu, Hongsheng; Pang, Hong; De Clercq, Patrick
2017-03-01
The specialist predatory ladybird Cryptolaemus montrouzieri is an effective natural enemy of mealybugs and plays a key role in the biological control of these pests. However, its mass production is complicated by the dependence on parallel cultures of mealybugs or the need for Ephestia kuehniella eggs as an expensive factitious prey. Here we developed a pollen-based artificial food for the predator to lower its dependence on natural prey. We found that this artificial diet was an effective alternative food for larvae and adults of this predator. The artificial food supported the development and reproduction of the predator not only in the first generation (F0) but also in the next generation (F1). Although the developmental time and preoviposition period of C. montrouzieri on the artificial food were ca 1.5 days and 4 days longer than on the natural prey, the citrus mealybug Planococcus citri, respectively, its immature survival, fecundity and egg hatch were similar to those on mealybugs. In addition, adult C. montrouzieri maintained on natural or artificial food had a similar starvation resistance. Our results suggest that the pollen-based artificial diet can be used as an alternative food in the rearing of C. montrouzieri, and indicate its potential to support the mass production and wider application of this predator in biological control programmes. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.
Unpredictable drug reaction in a child with Cornelia de Lange syndrome.
Stevic, Marija; Milojevic, Irina; Bokun, Zlatko; Simic, Dusica
2015-02-01
Preoperative use of midazolam sedation is mandatory during induction of anesthesia in noncooperative and hyperactive children to prevent possible obstacles. Unusual drug reactions rarely occur in patients undergoing anesthesia or in intensive care unit. This report describes an unpredictable drug reaction after a routine midazolam premedication in a patient with no history of allergy. There has been no literature data yet to show that midazolam can provoke respiratory problems in patients with Cornelia de Lange Syndrome. In our opinion midazolam should be avoided in patients with Cornelia de Lange Syndrome, which we enforced after first unpredictable reaction.
How unpredictable access to food increases the body fat of small passerines: A mechanistic approach.
Anselme, Patrick; Otto, Tobias; Güntürkün, Onur
2017-11-01
Unpredictable rewards increase the vigor of responses in autoshaping (a Pavlovian conditioning procedure) and are preferred to predictable rewards in free-choice tasks involving fixed- versus variable-delay schedules. The significance those behavioral properties may have in field conditions is currently unknown. However, it is noticeable that when exposed to unpredictable food, small passerines - such as robins, titmice, and starlings - get fatter than when food is abundant. In functional terms, fattening is viewed as an evolutionary strategy acting against the risk of starvation when food is in short supply. But this functional view does not explain the causal mechanisms by which small passerines come to be fatter under food uncertainty. Here, it is suggested that one of these causal mechanisms is that involved in behavioral invigoration and preference for food uncertainty in the laboratory. Based on a psychological theory of motivational changes under food uncertainty, we developed an integrative computational model to test this idea. We show that, for functional (adaptive) reasons, the excitatory property of reward unpredictability can underlie the propensity of wild birds to forage longer and/or more intensively in an unpredictable environment, with the consequence that they can put on more fat reserves. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Li, Junwei; Xie, Xiaoyong; Zhu, Changbo; Guo, Yongjian; Chen, Suwen
2017-10-01
Sipunculus nudus is an important economic species because of its high nutritional and medicinal values. The exploitation and utilization of S. nudus primarily occur in the coastal regions of the Beibu Gulf. However, wild resource of S. nudus is rapidly decreasing because of the overexploitation, which has led to considerable developments of artificial breeding techniques. The cultivation scale of S. nudus has increased in response to successful artificial breeding; however, methods for culturing S. nudus in tidal flats or ponds require further study. Most studies have focused on the breeding, nutrition, medical value and ecological impact of these worms. Studies on the distribution, sediment requirements, nutrition characteristics, breeding techniques and aquaculture ecology of this species are summarized in this paper to promote the development of the aquaculture industry for S. nudus. The high biomass of S. nudus in the Beibu Gulf is positively correlated with the sediment characteristics and water quality of the region. The production of peanut worm has improved to some extent through culturing; however, the nutrient value and ecological environment problems have been observed, which reflect the over exploitation of trace elements and the sediment. These problems will worsen unless they are resolved, and the release of organic materials, nitrogen and phosphorus during harvesting impacts the coastal environment. Moreover, genetic erosion is a potential risk for larvae in artificial breeding programs in tidal flats. Therefore, culturing and collecting methods should be improved and the wild resource conservation should be implemented to promote the sustainable development of the peanut worm.
Assessment of quality of water provided for wildlife in the Central Kalahari Game Reserve, Botswana
NASA Astrophysics Data System (ADS)
Selebatso, Moses; Maude, Glyn; Fynn, Richard W. S.
2018-06-01
Arid and semi-arid environments have low and unpredictable rainfall patterns resulting in limited availability of surface water for wildlife. In the Central Kalahari Game Reserve (CKGR) wildlife populations have lost access to natural surface water through cordon fences, livestock and human encroachment along the access routes. Artificial waterholes have been developed in the reserve to compensate for this loss. However, there have not been any assessments of the quality of water provided for wildlife and how that may be contributing to populations declines in the CKGR. We assessed water quality from 12 artificial waterholes against both Botswana and international livestock standards for drinking. Overall the quality of water provided is poor and poses a health risk to both animals and humans. Eight out of twelve boreholes tested exceeded the maximum acceptable Total Dissolved Solids (TDS) limits while three and four boreholes have toxic levels of lead and arsenic, respectively. Thus, pumping ground water could have more negative than positive impacts on wildlife thus defeating the intended management purpose. Failure to provide water of acceptable quality is a major concern for wildlife management in the CKGR and it may underlie some wildlife declines in the reserve. These findings confirm that restriction of populations from natural water sources create complex management challenges, especially where safe and sustainable alternative sources are scarce. Restriction of access of the population to natural water sources by fences and provision of poor quality water could compromise the overall fitness of wildlife populations and contribute to their decline.
Bolshevik Disease and Stalinist Terror: On the Historical Casuistry of Artificial Pneumothorax
Polianski, Igor J.
2015-01-01
From its initial development by Carlo Forlanini at the end of the nineteenth century until the advent of antibiotics in the 1940s, artificial pneumothorax was one of the most widely used treatments for pulmonary tuberculosis. However, there were strongly held reservations about this therapy because of its risks and side effects. In the Soviet Union under Stalin, such uncertainties became instruments of political denunciation. The leading Soviet pulmonary physician Volf S. Kholtsman (1886–1941) was alleged to have used the so-called ‘aristocratic therapy’ of artificial pneumothorax to kill prominent Bolsheviks. Drawing on documents from Stalin’s personal Secretariat, this historical study of the pneumothorax scandal contributes to the cultural history of tuberculosis, showing how it was instrumentalised for political purposes. PMID:25498436
Chang, Thomas M. S.
2013-01-01
The first experimental artificial red blood cells have all three major functions of red blood cells (rbc). However, the first practical one is a simple polyhemoglobin (PolyHb) that only has an oxygen-carrying function. This is now in routine clinical use in South Africa and Russia. An oxygen carrier with antioxidant functions, PolyHb-catalase-superoxide dismutase, can fulfill two of the three functions of rbc. Even more complete is one with all three functions of rbc in the form of PolyHb-catalase-superoxide dismutase-carbonic anhydrase. The most advanced ones are nanodimension artificial rbc with either PEG-lipid membrane or PEG-PLA polymermembrane. Extensions in to oxygen therapeutics include a PolyHb-tyrosinase that suppresses the growth of melanoma in a mice model. Another is a PolyHb-fibrinogen that is an oxygen carrier with platelet-like function. Research has now extended well beyond the original research on artificial rbc into many areas of artificial cells. These include nanoparticles, nanotubules, lipid vesicles, liposomes, polymer-tethered lipid vesicles, polymersomes, microcapsules, bioencapsulation, nanocapules, macroencapsulation, synthetic cells, and others. These are being used in nanotechnology, nanomedicine, regenerative medicine, enzyme/gene therapy, cell/stem cell therapy, biotechnology, drug delivery, hemoperfusion, nanosensers, and even by some groups in agriculture, industry, aquatic culture, nanocomputers, and nanorobotics. PMID:22409281
[Overview of the artificial enhancement and release of endemic freshwater fish in China].
Yang, Jun-Xing; Pan, Xiao-Fu; Chen, Xiao-Yong; Wang, Xiao-Ai; Zhao, Ya-Peng; Li, Jian-You; Li, Zai-Yun
2013-08-01
Due to declining fishery resources and the growing development of conservation aquaculture, artificial freshwater fish enhancement and releasing have begun to replace traditional means of recovering endemic and rare fish populations. Artificial proliferation can be beneficial both to endemic fish conservation and technical bottleneck breakthroughs. This overview presents a review of the latest research and the underlying principles behind the conservation implementation processes, as well as the research status of artificial enhancement and release of endangered freshwater fish species in China, such as Mylopharyngodon piceus, Ctenopharyngodon idellus, Hypophthalmichthys molitrix, H. nobilis, Acipenser sinensis, Myxocyprinus asiaticus, and Sinocyclocheilus grahami. The overview also presents evolutionarily significant units, sperm and egg quality, and cryopreservation technologies and cell cultures used in artificial enhancement and release, which help standardize genetic management and minimize the genetic differences between hatched and wild populations. Monitoring fish from cultivation to release is essential to evaluating wild population recovery and adjusting recovery plans. Moreover, the remaining problems of artificial releases are discussed in-depth, touching on issues such as the limitations of domestic hatching, the base number of wild populations necessary to the environment, the proper size at which to release juveniles' into the environment, the geographic confusion of populations, the contradictions in commercial fish selection and fish conservation, and "exotic species" invasion.
Artificial “ping-pong” cascade of PIWI-interacting RNA in silkworm cells
Shoji, Keisuke; Suzuki, Yutaka; Sugano, Sumio; Shimada, Toru; Katsuma, Susumu
2017-01-01
PIWI-interacting RNAs (piRNAs) play essential roles in the defense system against selfish elements in animal germline cells by cooperating with PIWI proteins. A subset of piRNAs is predicted to be generated via the “ping-pong” cascade, which is mainly controlled by two different PIWI proteins. Here we established a cell-based artificial piRNA production system using a silkworm ovarian cultured cell line that is believed to possess a complete piRNA pathway. In addition, we took advantage of a unique silkworm sex-determining one-to-one ping-pong piRNA pair, which enabled us to precisely monitor the behavior of individual artificial piRNAs. With this novel strategy, we successfully generated artificial piRNAs against endogenous protein-coding genes via the expected back-and-forth traveling mechanism. Furthermore, we detected “primary” piRNAs from the upstream region of the artificial “ping-pong” site in the endogenous gene. This artificial piRNA production system experimentally confirms the existence of the “ping-pong” cascade of piRNAs. Also, this system will enable us to identify the factors involved in both, or each, of the “ping” and “pong” cascades and the sequence features that are required for efficient piRNA production. PMID:27777367
Brazilian and Mexican experiences in the study of incipient domestication
2014-01-01
Background Studies of domestication enables a better understanding of human cultures, landscape changes according to peoples’ purposes, and evolutionary consequences of human actions on biodiversity. This review aimed at discussing concepts, hypotheses, and current trends in studies of domestication of plants, using examples of cases studied in regions of Mesoamerica and Brazil. We analyzed trends of ethnobiological studies contributing to document processes of domestication and to establish criteria for biodiversity conservation based on traditional ecological knowledge. Methods Based on reviewing our own and other authors’ studies we analyzed management patterns and evolutionary trends associated to domestication occurring at plant populations and landscape levels. Particularly, we systematized information documenting: ethnobotanical aspects about plant management and artificial selection mechanisms, morphological consequences of plant management, population genetics of wild and managed plant populations, trends of change in reproduction systems of plants associated to management, and other ecological and physiological aspects influenced by management and domestication. Results Based on the analysis of study cases of 20 native species of herbs, shrubs and trees we identified similar criteria of artificial selection in different cultural contexts of Mexico and Brazil. Similar evolutionary trends were also identified in morphology (selection in favor of gigantism of useful and correlated parts); organoleptic characteristics such as taste, toxicity, color, texture; reproductive biology, mainly breeding system, phenological changes, and population genetics aspects, maintenance or increasing of genetic diversity in managed populations, high gene flow with wild relatives and low structure maintained by artificial selection. Our review is a first attempt to unify research methods for analyzing a high diversity of processes. Further research should emphasize deeper analyses of contrasting and diverse cultural and ecological contexts for a better understanding of evolution under incipient processes of domestication. Conclusion Higher research effort is particularly required in Brazil, where studies on this topic are scarcer than in Mexico but where diversity of human cultures managing their also high plant resources diversity offer high potential for documenting the diversity of mechanisms of artificial selection and evolutionary trends. Comparisons and evaluations of incipient domestication in the regions studied as well as the Andean area would significantly contribute to understanding origins and diffusion of the experience of managing and domesticating plants. PMID:24694009
Artificial consciousness, artificial emotions, and autonomous robots.
Cardon, Alain
2006-12-01
Nowadays for robots, the notion of behavior is reduced to a simple factual concept at the level of the movements. On another hand, consciousness is a very cultural concept, founding the main property of human beings, according to themselves. We propose to develop a computable transposition of the consciousness concepts into artificial brains, able to express emotions and consciousness facts. The production of such artificial brains allows the intentional and really adaptive behavior for the autonomous robots. Such a system managing the robot's behavior will be made of two parts: the first one computes and generates, in a constructivist manner, a representation for the robot moving in its environment, and using symbols and concepts. The other part achieves the representation of the previous one using morphologies in a dynamic geometrical way. The robot's body will be seen for itself as the morphologic apprehension of its material substrata. The model goes strictly by the notion of massive multi-agent's organizations with a morphologic control.
Li, Hong; Ge, Yunsheng; Zhang, Pengyun; Wu, Lingxiang; Chen, Shiyi
2012-01-01
Surface coating with an organic layer-by-layer self-assembled template of chitosan and hyaluronic acid on a poly(ethylene terephthalate) (PET) artificial ligament was designed for the promotion and enhancement of graft-to-bone healing after artificial ligament implantation in a bone tunnel. The results of in vitro culturing of MC3T3-E1 mouse osteoblastic cells supported the hypothesis that the layer-by-layer coating of chitosan and hyaluronic acid could promote the cell compatibility of grafts and could promote osteoblast proliferation. A rabbit extra-articular tendon-to-bone healing model was used to evaluate the effect of this kind of surface-modified stainless artificial ligament in vivo. The final results proved that this organic compound coating could significantly promote and enhance new bone formation at the graft-bone interface histologically and, correspondingly, the experimental group with coating had significantly higher biomechanical properties compared with controls at 8 weeks (P < 0.05).
1986-06-23
to St. Louis Cathedral; they did so, again citing health hazards . However, in 1846, Wood built a cotton compress at the location despite the presence...price of meat has always been low, and that the artificial restrictions of commerce have prevented the development of other outlets (Robin 1966:114...relationships among the variables. The cultural resource professional will avoid pigeon -holing data gathering operations into unalterable research
Liu, Feng-Guo; Hu, Wen-Feng; Wang, Ji-Li; Wang, Peng; Gong, Yu; Tong, Li-Juan; Jiang, Bo; Zhang, Wei; Qin, Yi-Bin; Chen, Zhuo
2017-01-01
Abstract Background: Z-guggulsterone, an active compound extracted from the gum resin of the tree Commiphora mukul, has been shown to improve animal memory deficits via activating the brain-derived neurotrophic factor signaling pathway. Here, we investigated the antidepressant-like effect of Z-guggulsterone in a chronic unpredictable stress mouse model of depression. Methods: The effects of Z-guggulsterone were assessed in mice with the tail suspension test and forced swimming test. Z-guggulsterone was also investigated in the chronic unpredictable stress model of depression with fluoxetine as the positive control. Changes in hippocampal neurogenesis as well as the brain-derived neurotrophic factor signaling pathway after chronic unpredictable stress/Z-guggulsterone treatment were investigated. The tryptophan hydroxylase inhibitor and the tyrosine kinase B inhibitor were also used to explore the antidepressant-like mechanisms of Z-guggulsterone. Results: Z-guggulsterone (10, 30 mg/kg) administration protected the mice against the chronic unpredictable stress-induced increases in the immobile time in the tail suspension test and forced swimming test and also reversed the reduction in sucrose intake in sucrose preference experiment. Z-guggulsterone (10, 30 mg/kg) administration prevented the reductions in brain-derived neurotrophic factor protein expression levels as well as the phosphorylation levels of cAMP response element binding protein, extracellular signal-regulated kinase 1/2, and protein kinase B in the hippocampus and cortex induced by chronic unpredictable stress. Z-guggulsterone (10, 30 mg/kg) treatment also improved hippocampal neurogenesis in chronic unpredictable stress-treated mice. Blockade of the brain-derived neurotrophic factor signal, but not the monoaminergic system, attenuated the antidepressant-like effects of Z-guggulsterone. Conclusions: Z-guggulsterone exhibits antidepressant activity via activation of the brain-derived neurotrophic factor signaling pathway and upregulation of hippocampal neurogenesis. PMID:28339691
Three-dimensional (3D) printing of mouse primary hepatocytes to generate 3D hepatic structure.
Kim, Yohan; Kang, Kyojin; Jeong, Jaemin; Paik, Seung Sam; Kim, Ji Sook; Park, Su A; Kim, Wan Doo; Park, Jisun; Choi, Dongho
2017-02-01
The major problem in producing artificial livers is that primary hepatocytes cannot be cultured for many days. Recently, 3-dimensional (3D) printing technology draws attention and this technology regarded as a useful tool for current cell biology. By using the 3D bio-printing, these problems can be resolved. To generate 3D bio-printed structures (25 mm × 25 mm), cells-alginate constructs were fabricated by 3D bio-printing system. Mouse primary hepatocytes were isolated from the livers of 6-8 weeks old mice by a 2-step collagenase method. Samples of 4 × 10 7 hepatocytes with 80%-90% viability were printed with 3% alginate solution, and cultured with well-defined culture medium for primary hepatocytes. To confirm functional ability of hepatocytes cultured on 3D alginate scaffold, we conducted quantitative real-time polymerase chain reaction and immunofluorescence with hepatic marker genes. Isolated primary hepatocytes were printed with alginate. The 3D printed hepatocytes remained alive for 14 days. Gene expression levels of Albumin , HNF-4α and Foxa3 were gradually increased in the 3D structures. Immunofluorescence analysis showed that the primary hepatocytes produced hepatic-specific proteins over the same period of time. Our research indicates that 3D bio-printing technique can be used for long-term culture of primary hepatocytes. It can therefore be used for drug screening and as a potential method of producing artificial livers.
Zhang, L; Zhou, R; Niu, M; Zheng, J; Wu, C
2015-11-01
Artificial pit muds (APMs) is produced by peats, aged pit muds, yellow and black clays etc. and is one of essential factors for Luzhou-flavour liquor production. The microbial community of APMs significantly influence the quality of Luzhou-flavour liquor. The aim of this study was to investigate the differences in bacterial, archaeal and fungal community of APMs, starters and materials. Multiphase culture-independent technology were employed in this study, including nested PCR-denaturing gradient gel electrophoresis (nested PCR-DGGE), phospholipid fatty acid (PLFA), phospholipid ether lipids (PLEL) and fluorescence in situ hybridization (FISH) analysis. Results suggested that the microbial diversity significantly changed under environmental stress and different culture patterns during APMs cultivation. The dominant bacteria in APMs mainly fell into Clostridiales, Lactobacillales, Bacteroidales and Rhizobiales, Archaea affiliated with Methanomicrobiales and Methanosarcinales, and fungi belonged to Saccharomycetales and Eurotiales. Furthermore, the microbial community structures of APMs cultured by ground pile pattern were more similar with that of aged pit muds, meanwhile, the relative bands intensities of microbes, which are the main contributors for liquor brewing, increased with the culture times. Not only the niche selection and biogeochemical properties of APMs, but also the mutual collaboration and constraint between different microbes may result in enriching different liquor-brewing microbes into APMs. APM cultivation technology was necessary to promote enriching functional liquor-brewing microbes into APMs. These results may facilitate understanding the microbial succession during APMs manufacture. © 2015 The Society for Applied Microbiology.
Arcoleo, Kimberly; Zayas, Luis E; Hawthorne, April; Begay, Rachelle
2015-09-01
Patients' cultural health beliefs and behaviors may conflict with biomedical healthcare values and practices potentially leading to non-adherence with asthma treatment regimens. To optimize shared decision-making, healthcare providers should understand and be sensitive to these cultural beliefs and behaviors and negotiate an asthma management plan acceptable to parents. The purpose of this study was to obtain the perspective of Mexican mothers regarding (1) their experiences of living with a child with asthma, (2) their understanding of the nature of asthma, and (3) how their cultural beliefs influence asthma management. A qualitative, phenomenological study design was employed to assess mothers' lived experiences with and perceptions of their child's asthma. Individual in-depth interviews were conducted with a purposeful sample of 20 Mexican mothers of children ages 5-17 years with asthma. An inductive, theory-driven, phenomenological analysis approach was used to elicit thematic findings. Mothers expressed a symptomatic perception of asthma and limited understanding of the disease. Most believe the disease is present only when their child is symptomatic. Many are surprised and puzzled by the unpredictability of their child's asthma attacks, which they report as sometimes "silent". The inconsistency of triggers also leads to frustration and worry, which may reflect their concerns around daily controller medication use and preference for alternative illness management strategies. Our clinical encounters should be refocused to better understand the context of these families' lives and the cultural lens through which they view their child's asthma.
NASA Astrophysics Data System (ADS)
Li, Deren; Du, Zhiqiang; Zhu, Yixuan; Wang, Tingsong
2009-09-01
Considerable damage has been done to the cultural heritage sites around the world ranging from natural erosion to artificial destruction. With the development of information sciences, frontier technologies are actively introduced to help protect cultural heritage sites. The new concept of a Digital Cultural Heritage has been presented for culture protection and is gradually becoming an efficient method to solve or to remit various difficult problems. This paper puts forward a digitalization method for cultural heritage sites which rationally integrates and utilizes multiform surveying measurements. These techniques have been successfully implemented into two projects, namely the Digital Mogao Grottos and the Chi Lin Nunnery reconstruction. Our results prove that the concept of and the techniques utilized in Digital Cultural Heritage can not only contribute to research, preservation, management, interpretation, and representation of cultural heritages but can also help resolve the conflicts between tourism and protection.
NASA Astrophysics Data System (ADS)
Li, Deren; Du, Zhiqiang; Zhu, Yixuan; Wang, Tingsong
2010-11-01
Considerable damage has been done to the cultural heritage sites around the world ranging from natural erosion to artificial destruction. With the development of information sciences, frontier technologies are actively introduced to help protect cultural heritage sites. The new concept of a Digital Cultural Heritage has been presented for culture protection and is gradually becoming an efficient method to solve or to remit various difficult problems. This paper puts forward a digitalization method for cultural heritage sites which rationally integrates and utilizes multiform surveying measurements. These techniques have been successfully implemented into two projects, namely the Digital Mogao Grottos and the Chi Lin Nunnery reconstruction. Our results prove that the concept of and the techniques utilized in Digital Cultural Heritage can not only contribute to research, preservation, management, interpretation, and representation of cultural heritages but can also help resolve the conflicts between tourism and protection.
Application of a Terrestrial LIDAR System for Elevation Mapping in Terra Nova Bay, Antarctica.
Cho, Hyoungsig; Hong, Seunghwan; Kim, Sangmin; Park, Hyokeun; Park, Ilsuk; Sohn, Hong-Gyoo
2015-09-16
A terrestrial Light Detection and Ranging (LIDAR) system has high productivity and accuracy for topographic mapping, but the harsh conditions of Antarctica make LIDAR operation difficult. Low temperatures cause malfunctioning of the LIDAR system, and unpredictable strong winds can deteriorate data quality by irregularly shaking co-registration targets. For stable and efficient LIDAR operation in Antarctica, this study proposes and demonstrates the following practical solutions: (1) a lagging cover with a heating pack to maintain the temperature of the terrestrial LIDAR system; (2) co-registration using square planar targets and two-step point-merging methods based on extracted feature points and the Iterative Closest Point (ICP) algorithm; and (3) a georeferencing module consisting of an artificial target and a Global Navigation Satellite System (GNSS) receiver. The solutions were used to produce a topographic map for construction of the Jang Bogo Research Station in Terra Nova Bay, Antarctica. Co-registration and georeferencing precision reached 5 and 45 mm, respectively, and the accuracy of the Digital Elevation Model (DEM) generated from the LIDAR scanning data was ±27.7 cm.
Asynchronous hatching and food limitation: A test of Lack's hypothesis
Skagen, Susan Knight
1988-01-01
Lack's (1954, 1968) hypothesis that asynchronous hatching of altricial birds is an adaptive response to unpredictable food shortages during the breeding season was examined in the highly granivorous Zebra Finch (Poephila guttata). I compared growth and survival of nestlings in asynchronous and artificially created synchronous broods reared under food-limited and food-abundant conditions in an aviary. I also examined the role of parental experience on survival and growth of nestlings.There was no differential mortality of Zebra Finch nestlings due to either asynchrony or food abundance. Young in abundant food treatments grew more rapidly, however, than those in food-restricted treatments. Heaviest Zebra Finch nestlings in a brood grew more quickly than their lightest siblings when food was limited, supporting Lack's hypothesis. Further, differential survival of light and heavy siblings occurred when food was abundant, suggesting that asynchronous hatching can be maladaptive under some ecological conditions. Nestlings reared by inexperienced parents suffered greater mortality and slower growth when food was abundant than nestlings raised by experienced parents. Prefledging mass was correlated with size at adulthood
Advanced Software V&V for Civil Aviation and Autonomy
NASA Technical Reports Server (NTRS)
Brat, Guillaume P.
2017-01-01
With the advances in high-computing platform (e.g., advanced graphical processing units or multi-core processors), computationally-intensive software techniques such as the ones used in artificial intelligence or formal methods have provided us with an opportunity to further increase safety in the aviation industry. Some of these techniques have facilitated building safety at design time, like in aircraft engines or software verification and validation, and others can introduce safety benefits during operations as long as we adapt our processes. In this talk, I will present how NASA is taking advantage of these new software techniques to build in safety at design time through advanced software verification and validation, which can be applied earlier and earlier in the design life cycle and thus help also reduce the cost of aviation assurance. I will then show how run-time techniques (such as runtime assurance or data analytics) offer us a chance to catch even more complex problems, even in the face of changing and unpredictable environments. These new techniques will be extremely useful as our aviation systems become more complex and more autonomous.
ATLAS LTCS Vertically Challenged System Lessons Learned
NASA Technical Reports Server (NTRS)
Patel, Deepak; Garrison, Matt; Ku, Jentung
2014-01-01
Re-planning of LTCS TVAC testing and supporting RTA (Receiver Telescope Assembly) Test Plan and Procedure document preparation. The Laser Thermal Control System (LTCS) is designed to maintain the lasers onboard Advanced Topographic Laser Altimeter System (ATLAS) at their operational temperatures. In order to verify the functionality of the LTCS, a thermal balance test of the thermal hardware was performed. During the first cold start of the LTCS, the Loop Heat Pipe (LHP) was unable to control the laser mass simulators temperature. The control heaters were fully on and the loop temperature remained well below the desired setpoint. Thermal analysis of the loop did not show these results. This unpredicted behavior of the LTCS was brought up to a panel of LHP experts. Based on the testing and a review of all the data, there were multiple diagnostic performed in order to narrow down the cause. The prevailing theory is that gravity is causing oscillating flow within the loop, which artificially increased the control power needs. This resulted in a replan of the LTCS test flow and the addition of a GSE heater to allow vertical operation.
Vrana, N Engin; Builles, Nicolas; Justin, Virginie; Bednarz, Jurgen; Pellegrini, Graziella; Ferrari, Barbara; Damour, Odile; Hulmes, David J S; Hasirci, Vasif
2008-12-01
To develop an artificial cornea, the ability to coculture the different cell types present in the cornea is essential. Here the goal was to develop a full-thickness artificial cornea using an optimized collagen-chondroitin sulfate foam, with a thickness close to that of human cornea, by coculturing human corneal epithelial and stromal cells and transfected human endothelial cells. Corneal extracellular matrix was simulated by a porous collagen/glycosaminoglycan-based scaffold seeded with stromal keratocytes and then, successively, epithelial and endothelial cells. Scaffolds were characterized for bulk porosity and pore size distribution. The performance of the three-dimensional construct was studied by histology, immunofluorescence, and immunohistochemistry. The scaffold had 85% porosity and an average pore size of 62.1 microm. Keratocytes populated the scaffold and produced a newly synthesized extracellular matrix as characterized by immunohistochemistry. Even though the keratocytes lost their CD34 phenotype marker, the absence of smooth muscle actin fibers showed that these cells had not differentiated into myofibroblasts. The epithelial cells formed a stratified epithelium and began basement membrane deposition. An endothelial cell monolayer beneath the foam was also apparent. These results demonstrate that collagen-chondroitin sulfate scaffolds are good substrates for artificial cornea construction with good resilience, long-term culture capability, and handling properties.
Social network- and community-level influences on contraceptive use: evidence from rural Poland.
Colleran, Heidi; Mace, Ruth
2015-05-22
The diffusion of 'modern' contraceptives-as a proxy for the spread of low-fertility norms-has long interested researchers wishing to understand global fertility decline. A fundamental question is how local cultural norms and other people's behaviour influence the probability of contraceptive use, independent of women's socioeconomic and life-history characteristics. However, few studies have combined data at individual, social network and community levels to simultaneously capture multiple levels of influence. Fewer still have tested if the same predictors matter for different contraceptive types. Here, we use new data from 22 high-fertility communities in Poland to compare predictors of the use of (i) any contraceptives-a proxy for the decision to control fertility-with those of (ii) 'artificial' contraceptives-a subset of more culturally taboo methods. We find that the contraceptive behaviour of friends and family is more influential than are women's own characteristics and that community level characteristics additionally influence contraceptive use. Highly educated neighbours accelerate women's contraceptive use overall, but not their artificial method use. Highly religious neighbours slow women's artificial method use, but not their contraceptive use overall. Our results highlight different dimensions of sociocultural influence on contraceptive diffusion and suggest that these may be more influential than are individual characteristics. A comparative multilevel framework is needed to understand these dynamics.
Lawal, Oluwasola; Knobel, Hugo; Weda, Hans; Nijsen, Tamara M E; Goodacre, Royston; Fowler, Stephen J
2018-01-01
Infections such as ventilator-associated pneumonia (VAP) can be caused by one or more pathogens. Current methods for identifying these pathogenic microbes often require invasive sampling, and can be time consuming, due to the requirement for prolonged cultural enrichment along with selective and differential plating steps. This results in delays in diagnosis which in such critically ill patients can have potentially life-threatening consequences. Therefore, a non-invasive and timely diagnostic method is required. Detection of microbial volatile organic compounds (VOCs) in exhaled breath is proposed as an alternative method for identifying these pathogens and may distinguish between mono- and poly-microbial infections. To investigate volatile metabolites that discriminate between bacterial mono- and co-cultures. VAP-associated pathogens Enterobacter cloacae and Pseudomonas aeruginosa were cultured individually and together in artificial sputum medium for 24 h and their headspace was analysed for potential discriminatory VOCs by thermal desorption gas chromatography-mass spectrometry. Of the 70 VOCs putatively identified, 23 were found to significantly increase during bacterial culture (i.e. likely to be released during metabolism) and 13 decreased (i.e. likely consumed during metabolism). The other VOCs showed no transformation (similar concentrations observed as in the medium). Bacteria-specific VOCs including 2-methyl-1-propanol, 2-phenylethanol, and 3-methyl-1-butanol were observed in the headspace of axenic cultures of E. cloacae , and methyl 2-ethylhexanoate in the headspace of P. aeruginosa cultures which is novel to this investigation. Previously reported VOCs 1-undecene and pyrrole were also detected. The metabolites 2-methylbutyl acetate and methyl 2-methylbutyrate, which are reported to exhibit antimicrobial activity, were elevated in co-culture only. The observed VOCs were able to differentiate axenic and co-cultures. Validation of these markers in exhaled breath specimens could prove useful for timely pathogen identification and infection type diagnosis.
Unpredictable evolution in a 30-year study of Darwin's finches.
Grant, Peter R; Grant, B Rosemary
2002-04-26
Evolution can be predicted in the short term from a knowledge of selection and inheritance. However, in the long term evolution is unpredictable because environments, which determine the directions and magnitudes of selection coefficients, fluctuate unpredictably. These two features of evolution, the predictable and unpredictable, are demonstrated in a study of two populations of Darwin's finches on the Galápagos island of Daphne Major. From 1972 to 2001, Geospiza fortis (medium ground finch) and Geospiza scandens (cactus finch) changed several times in body size and two beak traits. Natural selection occurred frequently in both species and varied from unidirectional to oscillating, episodic to gradual. Hybridization occurred repeatedly though rarely, resulting in elevated phenotypic variances in G. scandens and a change in beak shape. The phenotypic states of both species at the end of the 30-year study could not have been predicted at the beginning. Continuous, long-term studies are needed to detect and interpret rare but important events and nonuniform evolutionary change.
Moberg, Christine A.; Bradford, Daniel E.; Kaye, Jesse T.; Curtin, John J.
2017-01-01
Stress plays a key role in addiction etiology and relapse. Rodent models posit that following repeated periods of alcohol and other drug intoxication, compensatory allostatic changes occur in the central nervous system (CNS) circuits involved in behavioral and emotional response to stressors. We examine a predicted manifestation of this neuroadaptation in recently abstinent alcohol dependent humans. Participants completed a translational laboratory task that uses startle potentiation to unpredictable (vs. predictable) stressors implicated in the putative CNS mechanisms that mediate this neuroadaptation. Alcohol dependent participants displayed significantly greater startle potentiation to unpredictable than predictable stressors relative to non-alcoholic controls. The size of this effect covaried with alcohol-related problems and degree of withdrawal syndrome. This supports the rodent model thesis of a sensitized stress response in abstinent alcoholics. However, this effect could also represent pre-morbid risk or mark more severe and/or comorbid psychopathology. Regardless, pharmacotherapy and psychological interventions may target unpredictable stressor response to reduce stress-induced relapse. PMID:28394145
Weak signal detection: A discrete window of opportunity for achieving 'Vision 90:90:90'?
Burman, Christopher J; Aphane, Marota; Delobelle, Peter
2016-01-01
UNAIDS' Vision 90:90:90 is a call to 'end AIDS'. Developing predictive foresight of the unpredictable changes that this journey will entail could contribute to the ambition of 'ending AIDS'. There are few opportunities for managing unpredictable changes. We introduce 'weak signal detection' as a potential opportunity to fill this void. Combining futures and complexity theory, we reflect on two pilot case studies that involved the Archetype Extraction technique and the SenseMaker(®) Collector(™) tool. Both the piloted techniques have the potentials to surface weak signals--but there is room for improvement. A management response to a complex weak signal requires pattern management, rather than an exclusive focus on behaviour management. Weak signal detection is a window of opportunity to improve resilience to unpredictable changes in the HIV/AIDS landscape that can both reduce the risk that emerges from the changes and increase the visibility of opportunities to exploit the unpredictable changes that could contribute to 'ending AIDS'.
Jeżewska, Maria; Grubman-Nowak, Marta; Leszczyñska, Irena; Jaremin, Bogdan
2012-01-01
The work of marine fishermen is considered one of the most dangerous and life-threatening professions all over the world. There are some common features of the fishing occupation, such as: exposure to cold, wind, rough seas, substantial participation of physical effort, frequency of injuries during work, unpredictability and abruptness of threats, equipment failure, everyday psychological stress, and constant economic pressure. At the same time, the specificity and variety of hazards, depending significantly on geographical-climate and cultural factors, makes the dissimilarity of problems and solutions substantial in different sectors of fishing. The present article is a review of the problems of Polish costal fishermen, referring to some local particularities within this extremely difficult profession requiring special predispositions.
Beller Lecture: Is Understanding the Past in Its Own Terms Understanding?
NASA Astrophysics Data System (ADS)
Wootton, David
History of Science is in a state of intellectual confusion symbolized by its hostility to what is called ``Whig history''. The fundamental issue is whether it is legitimate to use hindsight in the writing of history. In this lecture I will defend retrospective history in three key respects: a) retrospection is generally a legitimate procedure in historical writing, primarily because historical outcomes are often unintended and unpredictable; b) retrospection is particularly legitimate where science is concerned because scientific development is path dependent; c) restrospection is particularly legitimate in history of science because science progresses, and progress can only be identified retrospectively. Defending retrospection is entirely compatible with recognizing that science is culturally specific; thus retrospection need not involve anachronism. See www.inventionofscience.com
Where Creativity and Innovation are much Needed Fuels
NASA Astrophysics Data System (ADS)
Loreto, Vittorio
Our societies are being thoroughly transformed by the pervasive role technology is playing in our culture and everyday life. Nowadays the term techno-social systems is adopted to quickly refer to social systems in which the technology entangles, in an original and unpredictable way, cognitive, behavioral, and social aspects of human beings. This revolution does not come without a cost and in our complex world new global challenges always emerge that call for new paradigms and original thinking: climate change, global financial crises, global pandemics, growth of cities, urbanization, and migration patterns. In this framework we progressively face the need to increase the number of people able to imagine original and valuable solutions to sustain large human societies safely and prosperously...
Tessadori, Jacopo; Bisio, Marta; Martinoia, Sergio; Chiappalone, Michela
2012-01-01
Behaviors, from simple to most complex, require a two-way interaction with the environment and the contribution of different brain areas depending on the orchestrated activation of neuronal assemblies. In this work we present a new hybrid neuro-robotic architecture based on a neural controller bi-directionally connected to a virtual robot implementing a Braitenberg vehicle aimed at avoiding obstacles. The robot is characterized by proximity sensors and wheels, allowing it to navigate into a circular arena with obstacles of different sizes. As neural controller, we used hippocampal cultures dissociated from embryonic rats and kept alive over Micro Electrode Arrays (MEAs) for 3–8 weeks. The developed software architecture guarantees a bi-directional exchange of information between the natural and the artificial part by means of simple linear coding/decoding schemes. We used two different kinds of experimental preparation: “random” and “modular” populations. In the second case, the confinement was assured by a polydimethylsiloxane (PDMS) mask placed over the surface of the MEA device, thus defining two populations interconnected via specific microchannels. The main results of our study are: (i) neuronal cultures can be successfully interfaced to an artificial agent; (ii) modular networks show a different dynamics with respect to random culture, both in terms of spontaneous and evoked electrophysiological patterns; (iii) the robot performs better if a reinforcement learning paradigm (i.e., a tetanic stimulation delivered to the network following each collision) is activated, regardless of the modularity of the culture; (iv) the robot controlled by the modular network further enhances its capabilities in avoiding obstacles during the short-term plasticity trial. The developed paradigm offers a new framework for studying, in simplified model systems, neuro-artificial bi-directional interfaces for the development of new strategies for brain-machine interaction. PMID:23248586
Some remarks on the compatibility between determinism and unpredictability.
Franceschelli, Sara
2012-09-01
Determinism and unpredictability are compatible since deterministic flows can produce, if sensitive to initial conditions, unpredictable behaviors. Within this perspective, the notion of scenario to chaos transition offers a new form of predictability for the behavior of sensitive to initial condition systems under the variation of a control parameter. In this paper I first shed light on the genesis of this notion, based on a dynamical systems approach and on considerations of structural stability. I then suggest a link to the figure of epigenetic landscape, partially inspired by a dynamical systems perspective, and offering a theoretical framework to apprehend developmental noise. Copyright © 2012 Elsevier Ltd. All rights reserved.
Choi, Sungjin; Lee, Jongil; Igawa, Kazuyo; Suzuki, Shigeki; Mochizuki, Manabu; Nishimura, Ryohei; Chung, Ung-il; Sasaki, Nobuo
2011-12-01
Artificial bone implants are often incorporated with osteoinductive factors to facilitate early bone regeneration. Calcium phosphate, the main component in artificial bone implants, strongly binds these factors, and in a few cases, the incorporated proteins are not released from the implant under conditions of physiological pH, thereby leading to reduction in their osteoinductivity. In this study, we coated tailor-made bone implants with trehalose to facilitate the release of basic fibroblast growth factor (bFGF). In an in vitro study, mouse osteoblastic cells were separately cultured for 48 hr in a medium with a untreated implant (T-), trehalose-coated implant (T+), bFGF-incorporated implant (FT-), and bFGF-incorporated implant with trehalose coating (FT+). In the FT+ group, cell viability was significantly higher than that in the other groups (P<0.05). Scanning electron microscopy (SEM) and X-ray diffraction (XRD) revealed that trehalose effectively covered the surface of the artificial bone implant without affecting the crystallinity or the mechanical strength of the artificial bone implant. These results suggest that coating artificial bone implants with trehalose could limit the binding of bFGF to calcium phosphate.
Watanabe, K; Imase, M; Aoyagi, H; Ohmura, N; Saiki, H; Tanaka, H
2008-09-01
(i) Quantitative and qualitative analyses of photosynthetic metabolites of Chlorella sorokiniana and elucidation of the mechanism of their utilization by algal symbionts. (ii) Development of artificial medium that imitates photoautotroph-heterotroph interaction and investigation of its suitability for isolation of novel microbes from the environment. Various components, including free dissolved carbohydrates, nitrogenous compounds and vitamin, were detected and together contributed 11.1% (as carbon content) of the total photosynthetic metabolites in the medium. Utilization of these photosynthetic metabolites in algal culture broth by algal symbionts was studied. Many symbionts showed specific utilization patterns. A novel artificial extracellular released organic carbon medium, which imitated the nutritional conditions surrounding algae, was developed based on the pattern of utilization of the algal metabolites by the symbiotic heterotrophs. About 42.9% of the isolates were closely related to photoautotrophic-dependent and oligotrophic bacteria. With the novel artificial medium, it was possible to selectively isolate some bacterial strains. Synthetic bacterial growth medium is an important and basic tool for bacterial isolation from environmental samples. The current study shows that preferential separation of typical bacterial subset can be achieved by using artificial medium that mimics photosynthetic metabolites.
Lu, Zenghui; Shi, Ping; He, Yuanchuan; Zhang, Deli; He, Zongyi; Chen, Shijiang; Tu, Yongqin; Li, Li; Liu, Fei; Zeng, Wei
2015-01-01
Ophiocordyceps sinensis (syn. Cordyceps sinensis), well known as DongChongXiaCao (DCXC), is one of the most valuable traditional Chinese medicinal species. In this article, we provide a systematic review of natural enemies and diseases encountered in artificial cultivation of DCXC. Unfortunately, DCXC has been endangered over the past decades due to overharvesting and a worsening ecological environment. Therefore, the artificial cultivation of DCXC has been extensively investigated in recent years. Complete indoor artificial cultivation and semi-field cultivation are the two most common strategies used to cultivate DCXC. However, cultured DCXCs are often attacked by various natural enemies and diseases, which have resulted in substantial loss of the valuable medicinal resource. In this study, we have summarized the species of natural enemies and types of diseases confronted by DCXC. Twenty reported natural enemy species are categorized into four classes, one of which is reported for the first time in this study. Moreover, six microbial pathogens are also discussed. The recapitulation of the natural enemies and diseases in DCXC artificial cultivation not only promote the development of integrated pest management of DCXC cultivation but also provide important information to help preserve and develop this valuable resource.
Wen, Zhiqiang; Wu, Mianbin; Lin, Yijun; Yang, Lirong; Lin, Jianping; Cen, Peilin
2014-07-15
Butanol is an industrial commodity and also considered to be a more promising gasoline substitute compared to ethanol. Renewed attention has been paid to solvents (acetone, butanol and ethanol) production from the renewable and inexpensive substrates, for example, lignocellulose, on account of the depletion of oil resources, increasing gasoline prices and deteriorating environment. Limited to current tools for genetic manipulation, it is difficult to develop a genetically engineered microorganism with combined ability of lignocellulose utilization and solvents production. Mixed culture of cellulolytic microorganisms and solventogenic bacteria provides a more convenient and feasible approach for ABE fermentation due to the potential for synergistic utilization of the metabolic pathways of two organisms. But few bacteria pairs succeeded in producing biobutanol of high titer or high productivity without adding butyrate. The aim of this work was to use Clostridium cellulovorans 743B to saccharify lignocellulose and produce butyric acid, instead of adding cellulase and butyric acid to the medium, so that the soluble sugars and butyric acid generated can be subsequently utilized by Clostridium beijerinckii NCIMB 8052 to produce butanol in one pot reaction. A stable artificial symbiotic system was constructed by co-culturing a celluloytic, anaerobic, butyrate-producing mesophile (C. cellulovorans 743B) and a non-celluloytic, solventogenic bacterium (C. beijerinckii NCIMB 8052) to produce solvents by consolidated bioprocessing (CBP) with alkali extracted deshelled corn cobs (AECC), a low-cost renewable feedstock, as the sole carbon source. Under optimized conditions, the co-culture degraded 68.6 g/L AECC and produced 11.8 g/L solvents (2.64 g/L acetone, 8.30 g/L butanol and 0.87 g/L ethanol) in less than 80 h. Besides, a real-time PCR assay based on the 16S rRNA gene sequence was performed to study the dynamics of the abundance of each strain during the co-culturing process, which figured out the roles of each strain at different periods in the symbiosis. Our work illustrated the great potential of artificial symbiosis in biofuel production from lignocellulosic biomass by CBP. The dynamics of the abundance of C. beijerinckii and C. cellulovorans revealed mechanisms of cooperation and competition between the two strains during the co-culture process.
44 CFR 64.3 - Flood Insurance Maps.
Code of Federal Regulations, 2010 CFR
2010-10-01
... with water surface elevations determined A0 Area of special flood hazards having shallow water depths... insurance rating purposes AH Areas of special flood hazards having shallow water depths and/or unpredictable... of special flood hazards having shallow water depths and/or unpredictable flow paths between (1) and...
Eliminating Unpredictable Variation through Iterated Learning
ERIC Educational Resources Information Center
Smith, Kenny; Wonnacott, Elizabeth
2010-01-01
Human languages may be shaped not only by the (individual psychological) processes of language acquisition, but also by population-level processes arising from repeated language learning and use. One prevalent feature of natural languages is that they avoid unpredictable variation. The current work explores whether linguistic predictability might…
Stevens, Elizabeth S; Weinberg, Anna; Nelson, Brady D; Meissel, Emily E E; Shankman, Stewart A
2018-03-01
Attention-related abnormalities are key components of the abnormal defensive responding observed in panic disorder (PD). Although behavioral studies have found aberrant attentional biases towards threat in PD, psychophysiological studies have been mixed. Predictability of threat, an important feature of threat processing, may have contributed to these mixed findings. Additionally, anxiety sensitivity, a dimensional trait associated with PD, may yield stronger associations with cognitive processes than categorical diagnoses of PD. In this study, 171 participants with PD and/or depression and healthy controls completed a task that differentiated anticipation of predictable vs. unpredictable shocks, while startle eyeblink and event-related potentials (ERPs [N100, P300]) were recorded. In all participants, relative to the control condition, probe N100 was enhanced to both predictable and unpredictable threat, whereas P300 suppression was unique to predictable threat. Probe N100, but not P300, was associated with startle eyeblink during both threatening conditions, and was strongest for unpredictable threat. PD was not associated with ERPs, but anxiety sensitivity (physical concerns) was positively associated with probe N100 (indicating reduced responding) in the unpredictable condition independent of PD diagnosis. Vulnerability to panic-related psychopathology may be characterized by aberrant early processing of threat, which may be especially evident during anticipation of unpredictable threats. Copyright © 2017 Elsevier Ltd. All rights reserved.
Dread of uncertain pain: An event-related potential study
Huang, Yujing; Shang, Qian; Dai, Shenyi; Ma, Qingguo
2017-01-01
Humans experience more stress about uncertain situations than certain situations. However, the neural mechanism underlying the uncertainty of a negative stimulus has not been determined. In the present study, event-related potential was recorded to examine neural responses during the dread of unpredictable pain. We used a cueing paradigm in which predictable cues were always followed by electric shocks, unpredictable cues by electric shocks at a 50/50 ratio and safe cues by no electric shock. Visual analogue scales following electric shocks were presented to quantify subjective anxiety levels. The behavioral results showed that unpredictable cues evoked high-level anxiety compared with predictable cues in both painful and unpainful stimulation conditions. More importantly, the ERPs results revealed that unpredictable cues elicited a larger P200 at parietal sites than predictable cues. In addition, unpredictable cues evoked larger P200 compared with safe cues at frontal electrodes and compared with predictable cues at parietal electrodes. In addition, larger P3b and LPP were observed during perception of safe cues compared with predictable cues at frontal and central electrodes. The similar P3b effect was also revealed in the left sites. The present study underlined that the uncertain dread of pain was associated with threat appraisal process in pain system. These findings on early event-related potentials were significant for a neural marker and development of therapeutic interventions. PMID:28832607
Kato, Yuka; Iwata, Takanori; Washio, Kaoru; Yoshida, Toshiyuki; Kuroda, Hozue; Morikawa, Shunichi; Hamada, Mariko; Ikura, Kazuki; Kaibuchi, Nobuyuki; Yamato, Masayuki; Okano, Teruo; Uchigata, Yasuko
2017-08-04
Artificial skin has achieved considerable therapeutic results in clinical practice. However, artificial skin treatments for wounds in diabetic patients with impeded blood flow or with large wounds might be prolonged. Cell-based therapies have appeared as a new technique for the treatment of diabetic ulcers, and cell-sheet engineering has improved the efficacy of cell transplantation. A number of reports have suggested that adipose-derived stem cells (ASCs), a type of mesenchymal stromal cell (MSC), exhibit therapeutic potential due to their relative abundance in adipose tissue and their accessibility for collection when compared to MSCs from other tissues. Therefore, ASCs appear to be a good source of stem cells for therapeutic use. In this study, ASC sheets from the epididymal adipose fat of normal Lewis rats were successfully created using temperature-responsive culture dishes and normal culture medium containing ascorbic acid. The ASC sheets were transplanted into Zucker diabetic fatty (ZDF) rats, a rat model of type 2 diabetes and obesity, that exhibit diminished wound healing. A wound was created on the posterior cranial surface, ASC sheets were transplanted into the wound, and a bilayer artificial skin was used to cover the sheets. ZDF rats that received ASC sheets had better wound healing than ZDF rats without the transplantation of ASC sheets. This approach was limited because ASC sheets are sensitive to dry conditions, requiring the maintenance of a moist wound environment. Therefore, artificial skin was used to cover the ASC sheet to prevent drying. The allogenic transplantation of ASC sheets in combination with artificial skin might also be applicable to other intractable ulcers or burns, such as those observed with peripheral arterial disease and collagen disease, and might be administered to patients who are undernourished or are using steroids. Thus, this treatment might be the first step towards improving the therapeutic options for diabetic wound healing.
Persistence of pentolite (PETN and TNT) in soil microcosms and microbial enrichment cultures.
Arbeli, Ziv; Garcia-Bonilla, Erika; Pardo, Cindy; Hidalgo, Kelly; Velásquez, Trigal; Peña, Luis; C, Eliana Ramos; Avila-Arias, Helena; Molano-Gonzalez, Nicolás; Brandão, Pedro F B; Roldan, Fabio
2016-05-01
Pentolite is a mixture (1:1) of 2,4,6-trinitrotoluene (TNT) and pentaerythritol tetranitrate (PETN), and little is known about its fate in the environment. This study was aimed to determine the dissipation of pentolite in soils under laboratory conditions. Microcosm experiments conducted with two soils demonstrated that dissipation rate of PETN was significantly slower than that of TNT. Interestingly, the dissipation of PETN was enhanced by the presence of TNT, while PETN did not enhanced the dissipation of TNT. Pentolite dissipation rate was significantly faster under biostimulation treatment (addition of carbon source) in soil from the artificial wetland, while no such stimulation was observed in soil from detonation field. In addition, the dissipation rate of TNT and PETN in soil from artificial wetland under biostimulation was significantly faster than the equivalent abiotic control, although it seems that non-biological processes might also be important for the dissipation of TNT and PETN. Transformation of PETN was also slower during establishment of enrichment culture using pentolite as the sole nitrogen source. In addition, transformation of these explosives was gradually reduced and practically stopped after the forth cultures transfer (80 days). DGGE analysis of bacterial communities from these cultures indicates that all consortia were dominated by bacteria from the order Burkholderiales and Rhodanobacter. In conclusion, our results suggest that PETN might be more persistent than TNT.
Bio-Source of di-n-butyl phthalate production by filamentous fungi
NASA Astrophysics Data System (ADS)
Tian, Congkui; Ni, Jinren; Chang, Fang; Liu, Sitong; Xu, Nan; Sun, Weiling; Xie, Yuan; Guo, Yongzhao; Ma, Yanrong; Yang, Zhenxing; Dang, Chenyuan; Huang, Yuefei; Tian, Zhexian; Wang, Yiping
2016-02-01
Although DBP (di-n-butyl phthalate) is commonly encountered as an artificially-synthesized plasticizer with potential to impair fertility, we confirm that it can also be biosynthesized as microbial secondary metabolites from naturally occurring filamentous fungi strains cultured either in an artificial medium or natural water. Using the excreted crude enzyme from the fungi for catalyzing a variety of substrates, we found that the fungal generation of DBP was largely through shikimic acid pathway, which was assembled by phthalic acid with butyl alcohol through esterification. The DBP production ability of the fungi was primarily influenced by fungal spore density and incubation temperature. This study indicates an important alternative natural waterborne source of DBP in addition to artificial synthesis, which implied fungal contribution must be highlighted for future source control and risk management of DBP.
Microwave sterilization of plastic tissue culture vessels for reuse.
Sanborn, M R; Wan, S K; Bulard, R
1982-10-01
A simple protocol has been developed for recycling plastic tissue culture vessels. The killing properties of microwaves were used to decontaminate plastic tissue culture vessels for reuse. Nine bacterial cultures, four gram-negative and five gram-positive genera, including two Bacillus species, were used to artificially contaminate tissue culture vessels. The microwaves produced by a "home-type" microwave oven (2.45 gHz) were able to decontaminate the vessels with a 3-min exposure. The same exposure time was also used to completely inactivate the following three test viruses: polio type 1, parainfluenza type 1 (Sendai), and bacteriophage T4. The recycling procedure did not reduce the attachment and proliferation of the following cell types: primary chicken and turkey embryo, HEp-2, Vero, BGMK, and MK-2.
Langhammer, Penny F; Lips, Karen R; Burrowes, Patricia A; Tunstall, Tate; Palmer, Crystal M; Collins, James P
2013-01-01
Laboratory investigations into the amphibian chytrid fungus, Batrachochytrium dendrobatidis (Bd), have accelerated recently, given the pathogen's role in causing the global decline and extinction of amphibians. Studies in which host animals were exposed to Bd have largely assumed that lab-maintained pathogen cultures retained the infective and pathogenic properties of wild isolates. Attenuated pathogenicity is common in artificially maintained cultures of other pathogenic fungi, but to date, it is unknown whether, and to what degree, Bd might change in culture. We compared zoospore production over time in two samples of a single Bd isolate having different passage histories: one maintained in artificial media for more than six years (JEL427-P39), and one recently thawed from cryopreserved stock (JEL427-P9). In a common garden experiment, we then exposed two different amphibian species, Eleutherodactylus coqui and Atelopus zeteki, to both cultures to test whether Bd attenuates in pathogenicity with in vitro passages. The culture with the shorter passage history, JEL427-P9, had significantly greater zoospore densities over time compared to JEL427-P39. This difference in zoospore production was associated with a difference in pathogenicity for a susceptible amphibian species, indicating that fecundity may be an important virulence factor for Bd. In the 130-day experiment, Atelopus zeteki frogs exposed to the JEL427-P9 culture experienced higher average infection intensity and 100% mortality, compared with 60% mortality for frogs exposed to JEL427-P39. This effect was not observed with Eleutherodactylus coqui, which was able to clear infection. We hypothesize that the differences in phenotypic performance observed with Atelopus zeteki are rooted in changes of the Bd genome. Future investigations enabled by this study will focus on the underlying mechanisms of Bd pathogenicity.
Prasad, Archana; Prakash, Om; Mehrotra, Shakti; Khan, Feroz; Mathur, Ajay Kumar; Mathur, Archana
2017-01-01
An artificial neural network (ANN)-based modelling approach is used to determine the synergistic effect of five major components of growth medium (Mg, Cu, Zn, nitrate and sucrose) on improved in vitro biomass yield in multiple shoot cultures of Centella asiatica. The back propagation neural network (BPNN) was employed to predict optimal biomass accumulation in terms of growth index over a defined culture duration of 35 days. The four variable concentrations of five media components, i.e. MgSO 4 (0, 0.75, 1.5, 3.0 mM), ZnSO 4 (0, 15, 30, 60 μM), CuSO 4 (0, 0.05, 0.1, 0.2 μM), NO 3 (20, 30, 40, 60 mM) and sucrose (1, 3, 5, 7 %, w/v) were taken as inputs for the ANN model. The designed model was evaluated by performing three different sets of validation experiments that indicated a greater similarity between the target and predicted dataset. The results of the modelling experiment suggested that 1.5 mM Mg, 30 μM Zn, 0.1 μM Cu, 40 mM NO 3 and 6 % (w/v) sucrose were the respective optimal concentrations of the tested medium components for achieving maximum growth index of 1654.46 with high centelloside yield (62.37 mg DW/culture) in the cultured multiple shoots. This study can facilitate the generation of higher biomass of uniform, clean, good quality C. asiatica herb that can efficiently be utilized by pharmaceutical industries.
Disease in a more variable and unpredictable climate
NASA Astrophysics Data System (ADS)
McMahon, T. A.; Raffel, T.; Rohr, J. R.; Halstead, N.; Venesky, M.; Romansic, J.
2014-12-01
Global climate change is shifting the dynamics of infectious diseases of humans and wildlife with potential adverse consequences for disease control. Despite this, the role of global climate change in the decline of biodiversity and the emergence of infectious diseases remains controversial. Climate change is expected to increase climate variability in addition to increasing mean temperatures, making climate less predictable. However, few empirical or theoretical studies have considered the effects of climate variability or predictability on disease, despite it being likely that hosts and parasites will have differential responses to climatic shifts. Here we present a theoretical framework for how temperature variation and its predictability influence disease risk by affecting host and parasite acclimation responses. Laboratory experiments and field data on disease-associated frog declines in Latin America support this framework and provide evidence that unpredictable temperature fluctuations, on both monthly and diurnal timescales, decrease frog resistance to the pathogenic chytrid fungus Batrachochytrium dendrobatidis (Bd). Furthermore, the pattern of temperature-dependent growth of the fungus on frogs was inconsistent with the pattern of Bd growth in culture, emphasizing the importance of accounting for the host-parasite interaction when predicting climate-dependent disease dynamics. Consistent with our laboratory experiments, increased regional temperature variability associated with global El Niño climatic events was the best predictor of widespread amphibian losses in the genus Atelopus. Thus, incorporating the effects of small-scale temporal variability in climate can greatly improve our ability to predict the effects of climate change on disease.
Hasan, Shirin; Fatima, Naureen; Bilal, Nayeem; Suhail, Nida; Fatima, Sabiha; Morgan, Enas N; Aldebasy, Yousef; Alzohairy, Mohammad A; Banu, Naheed
2013-06-01
Dietary restriction (DR) lowers steady-state levels of oxidative stress and alters behavioral, physiological and biochemical responses in mammals. However, various factors effect its application in humans like socio-cultural, appetite and the daily life stress. Physiological and psychological stress owing to fast-paced lifestyles, translates into oxidative stress. In this work, the role of chronic unpredictable stress (CUS) on the effects of short term DR in mice in terms of biochemical and oxidative stress parameters was investigated. Further, the modulatory role of multivitamin-mineral supplement (MVM) on CUS and DR induced biochemical changes was studied to delineate the role of micronutrient supplementation. DR treatment increased the antioxidant status in the circulation and liver of mice but in the presence of chronic stressors there was a significant shift towards the pro-oxidant state. A decrease was found in the activities of antioxidant enzymes superoxide dismutase, catalase, and glutathione-S-transferase and glutathione reductase in the rats exposed to CUS with DR (CUS+DR), with an increased malondialdehyde and a decreased glutathione (GSH) levels as compared to the controls. Liver function enzymes-glutamate oxaloacetate transaminase and glutamate pyruvate transaminase were increased and a significant DNA damage was observed. Oral MVM supplement significantly improved this oxidative deterioration. Hence, MVM supplementation appears to potentially offer an effective intervention in the DR regimen to combat daily life physical and mental stress. Copyright © 2013 Elsevier Ltd. All rights reserved.
Parental concerns towards children and adolescents with epilepsy in Sri Lanka--Qualitative study.
Murugupillai, Roshini; Wanigasinghe, Jithangi; Muniyandi, Ravi; Arambepola, Carukshi
2016-01-01
Social, cultural, psychological and many other factors significantly impact the lives of epileptic children and their families. Parental concerns towards their children are less known in south Asian children with epilepsy. We aimed to identify the parental concerns regarding their children and adolescents with epilepsy in Sri Lanka. We carried out qualitative study in 3 districts of Sri Lanka, comprising 16 in-depth interviews with parents of children and adolescents with epilepsy and 3 focus group discussions with primary caregivers of epileptic children and key informants (schoolteachers, public health staffs). Content analysis of the interview data was performed. Parental concerns were spread among seven themes that emerged from the content analysis. These concerns were about the child's functioning in areas such as physical, behavioural, psychological and social, education, concerns related to anti-epileptic therapy and epilepsy as a disease. Parents were more concerned about their child's safety, educational achievements and future prospects in terms of employment and marriage. Unpredictability of seizures, fear of stigma and unawareness of epilepsy were the main reasons voiced by the parents for having such concerns. Increased concern and perception of vulnerability was seen among parents whose children had epilepsy and co-morbid illness. Parental concerns towards their children and adolescents show a multidimensional construct. Unpredictability of seizures, fear of stigma and unawareness of epilepsy were identified as key influential factors in moulding the parental concerns. Copyright © 2015. Published by Elsevier Ltd.
Sukirno, Sukirno; Situmorang, J; Sumarmi, S; Soesilohadi, R C Hidayat; Pratiwi, R; Sukirno, Sukirno; Situmorang, J; Sumarmi, S; Soesilohadi, R C Hidayat; Pratiwi, R
2013-12-01
The objective of this research was to evaluate artificial diets that can be used to successfully culture the atlas silk moth, Attacus atlas L. (Lepidoptera: Saturniidae) indoors. Four plant species were evaluated as the basic component of each diet, barringtonia (Barringtonia asiatica), cheesewood (Nauclea orientalis), soursop (Annona muricata), and mahogany (Swietenia mahagoni). Evaluation of the nutritional value of each diet was determined by an analysis of the hemolymph proteins of sixth instars using the Folin-Ciocalteu assay. Survivorship, cocoon quality, and hemolymph protein content of larvae fed the barringtonia diet were higher than those of larvae fed mahogany-, cheesewood-, and soursop-based artificial diets. The average adult emergence of those fed the barringtonia-based diet was 74.5%. The weights of the cocoon in this treatment with the pupa and the empty cocoons were 7.0 and 1.1 g, respectively. Hemolymph of the larvae fed the barringtonia-based artificial diet had the highest concentration of protein with an average of 28.06 mg/ml. The atlas moth reared on the barringtonia-based artificial diet was comparable with those reared only on barringtonia leaves. However, the weight of empty cocoons, adult wingspan, and amount of hemolymph protein were lower than in those reared on barringtonia leaves only. This may suggest that the artificial barringtonia-based diet requires additional protein for maximum efficiency.
Language/culture/mind/brain. Progress at the margins between disciplines.
Kuhl, P K; Tsao, F M; Liu, H M; Zhang, Y; De Boer, B
2001-05-01
At the forefront of research on language are new data demonstrating infants' strategies in the early acquisition of language. The data show that infants perceptually "map" critical aspects of ambient language in the first year of life before they can speak. Statistical and abstract properties of speech are picked up through exposure to ambient language. Moreover, linguistic experience alters infants' perception of speech, warping perception in a way that enhances native-language speech processing. Infants' strategies are unexpected and unpredicted by historical views. At the same time, research in three additional disciplines is contributing to our understanding of language and its acquisition by children. Cultural anthropologists are demonstrating the universality of adult speech behavior when addressing infants and children across cultures, and this is creating a new view of the role adult speakers play in bringing about language in the child. Neuroscientists, using the techniques of modern brain imaging, are revealing the temporal and structural aspects of language processing by the brain and suggesting new views of the critical period for language. Computer scientists, modeling the computational aspects of childrens' language acquisition, are meeting success using biologically inspired neural networks. Although a consilient view cannot yet be offered, the cross-disciplinary interaction now seen among scientists pursuing one of humans' greatest achievements, language, is quite promising.
Growth of Piscirickettsia salmonis on Enriched Blood Agar
USDA-ARS?s Scientific Manuscript database
Piscirickettsia salmonis is the etiologic agent of piscirickettsiosis, an economically significant disease of fish. Isolation of P. salmonis by culturing on fish cell lines has been the standard technique since the initial isolation of the organism. The ability to grow P. salmonis on artificial medi...
ERIC Educational Resources Information Center
Belsky, Jay; Schlomer, Gabriel L.; Ellis, Bruce J.
2012-01-01
Drawing on life history theory, Ellis and associates' (2009) recent across- and within-species analysis of ecological effects on reproductive development highlighted two fundamental dimensions of environmental variation and influence: harshness and unpredictability. To evaluate the unique contributions of these factors, the authors of present…
Unpredictable and Uncontrollable Events: A New Perspective on Experimental Neurosis
ERIC Educational Resources Information Center
Kihlstrom, John F.; Mineka, Susan
1978-01-01
Recent work has shown that unpredictable and/or uncontrollable events can produce a variety of cognitive, affective, and somatic disturbances to the organism. These disturbances are compared to and found to be quite similar to the symptoms of the classic cases of experimental neurosis described by Pavlov, Gantt, Liddell, Masserman, and Wolpe.…
The Effects of Cognitive Readiness in a Surface Warfare Simulation
ERIC Educational Resources Information Center
Ayala, Donna
2008-01-01
This study investigated the effects of cognitive readiness in a Navy simulated environment, the simulation being the Multi-Mission Team Trainer. The research question that drove this study was: will simulations increase cognitive readiness? One of the tasks of Navy sailors is to deal with unpredictable events. Unpredictability in the military is…
Weak signal detection: A discrete window of opportunity for achieving ‘Vision 90:90:90’?
Burman, Christopher J.; Aphane, Marota; Delobelle, Peter
2016-01-01
Abstract Introduction: UNAIDS’ Vision 90:90:90 is a call to ‘end AIDS’. Developing predictive foresight of the unpredictable changes that this journey will entail could contribute to the ambition of ‘ending AIDS’. There are few opportunities for managing unpredictable changes. We introduce ‘weak signal detection’ as a potential opportunity to fill this void. Method: Combining futures and complexity theory, we reflect on two pilot case studies that involved the Archetype Extraction technique and the SenseMaker® Collector™ tool. Results: Both the piloted techniques have the potentials to surface weak signals – but there is room for improvement. Discussion: A management response to a complex weak signal requires pattern management, rather than an exclusive focus on behaviour management. Conclusion: Weak signal detection is a window of opportunity to improve resilience to unpredictable changes in the HIV/AIDS landscape that can both reduce the risk that emerges from the changes and increase the visibility of opportunities to exploit the unpredictable changes that could contribute to ‘ending AIDS’. PMID:26821952
Mass cultures of marine algae for energy farming in coastal deserts
NASA Astrophysics Data System (ADS)
Wagener, K.
1983-09-01
This paper provides a description of construction and subsequent operation of a seawater based system for biomass farming of micro-algae. Seawater was pumped through shallow artificial ponds located in coastal areas of Calabria, Italy. We describe pond construction, mixing procedure for micro algae mass cultures, optimization of the carbon and mineral nutrient budget, potential algal yields, methods for harvesting micro-algae, a source of energy to run the seawater pumps, and environmental variables of the pond system under subtropical conditions of Calabria, Italy.
THE SURVIVAL OF YELLOW FEVER VIRUS IN CULTURES
Lewis, Paul A.
1930-01-01
1. The virus of yellow fever has been found to survive in artificial culture media for at least 12 days at a temperature of 35°C. No visible growth has been present and no reproduction of the virus has been demonstrated. 2. Infections have been obtained in rhesus monkeys with two strains of virus in quantities as small as 0.00001 cc. of infectious blood, and with one strain in an amount probably as minute as 0.000001 cc. PMID:19869744
Growing Three-Dimensional Cartilage-Cell Cultures
NASA Technical Reports Server (NTRS)
Spaulding, Glenn F.; Prewett, Tacey L.; Goodwin, Thomas J.
1995-01-01
Process for growing three-dimensional cultures of mammalian cartilage from normal mammalian cells devised. Effected using horizontal rotating bioreactor described in companion article, "Simplified Bioreactor for Growing Mammalian Cells" (MSC-22060). Bioreactor provides quiescent environment with generous supplies of nutrient and oxygen. Initiated with noncartilage cells. Artificially grown tissue resembles that in mammalian cartilage. Potential use in developing therapies for damage to cartilage by joint and back injuries and by such inflammatory diseases as arthritis and temporal-mandibular joint disease. Also used to test nonsteroid anti-inflammation medicines.
Living with advanced Parkinson's disease: a constant struggle with unpredictability.
Haahr, Anita; Kirkevold, Marit; Hall, Elisabeth O C; Ostergaard, Karen
2011-02-01
This paper is a report of an exploration of patients' lifeworld and way of managing life with advanced Parkinson's disease prior to Deep Brain Stimulation and what they expect from life following this treatment. Parkinson's disease is a progressive neurodegenerative disease, which is initially well-treated with L-dopa. Living with Parkinson's disease means living with the experience of continuous loss of independence and self-esteem and unpredictable ON/OFF phenomena. Thus, in the advanced stage of the disease, treatment with Deep Brain Stimulation may become relevant. Eleven patients eligible for Deep Brain Stimulation were interviewed prior to treatment. Data were collected in 2007 and analysed according to the hermeneutic phenomenological methodology of van Manen, using the four existentials as analytic tools. Living with advanced Parkinson's disease can be described as the experience of living with and managing unpredictability. The disease gradually took over, and participants had to struggle with unpredictability on a daily basis. Themes in relation to this were: The body - setting the agenda, Always a struggle to be on time, Living in dependence and compromise - being a burden, and Living with restrained space and changes in social life. Parkinson's disease leads to profound bodily restrictions. Living with an unpredictable body affects all aspects of life, and nurses need to be aware of the impact the disease has on the entire lifeworld, and how this may affect the way treatment is perceived. © 2010 Blackwell Publishing Ltd.
The relationship between dlPFC activity during unpredictable threat and CO2-induced panic symptoms.
Balderston, Nicholas L; Liu, Jeffrey; Roberson-Nay, Roxann; Ernst, Monique; Grillon, Christian
2017-11-30
Panic disorder is characterized by sudden, repeated, and unexpected attacks of intense fear and overwhelming anxiety about when another attack may strike. Patients with panic disorder and healthy individuals with a history of panic attacks show a hypersensitivity to unpredictable threats, suggesting a possible link between panic and sustained anxiety. The purpose of this study was to determine the degree to which induced symptoms of panic relate to fear and anxiety, as well as activity in the neural systems that mediate and regulate these affective states. Psychological and physiological symptoms of panic were assessed during an 8-min 7.5% CO 2 challenge task. Psychological, physiological, and neural symptoms of fear and anxiety were measured during two sessions (one psychophysiology and one functional magnetic resonance imaging where subjects experienced several blocks of no threat (N), predictable shock (P), and unpredictable shock (U; NPU threat task). We used a principle component analysis to characterize panic susceptibility (PS), and found that PS significantly predicted dorsolateral prefrontal cortex (dlPFC) activity to the unpredictable cue during the NPU threat task. When examining the weighted beta coefficients from this analysis, we observed that self-reported fear/anxiety during the CO 2 challenge negatively loaded onto dlPFC activity during the NPU task. Consistent with this observation, dlPFC activity during the unpredictable cue was also negatively correlated with anxiety during the NPU sessions. Together, these results suggest that panic symptoms and anxiety are regulated by the same prefrontal cognitive control system.
Measuring anxious responses to predictable and unpredictable threat in children and adolescents
Schmitz, Anja; Merikangas, Kathleen; Swendsen, Haruka; Cui, Lihong; Heaton, Leanne; Grillon, Christian
2011-01-01
Research has highlighted the need for new methods to assess emotions in children on multiple levels in order to gain better insight into the complex processes of emotional development. The startle reflex is a unique translational tool that has been utilized to study physiological processes during fear and anxiety in rodents and in human subjects. However, it has been challenging to implement developmentally-appropriate startle experiments in children. This paper describes a procedure that uses predictable and unpredictable aversive events to distinguish between phasic fear and sustained anxiety in children and adolescents. We investigated anxious responses, as measured with the startle reflex, in youth (N = 36, mean age[range] = 12.63 [7–17]) across three conditions: no aversive events (N), predictable aversive events (P), and unpredictable aversive events (U). Short-duration cues were presented several times in each condition. Aversive events were signaled by the cues in P, but were presented randomly in U. Participants showed fear-potentiated startle to the threat cue in P. Startle responses were also elevated between cues in U compared to N, suggesting that unpredictable aversive events can evoke a sustained state of anxiety in youth. This latter effect was influenced by sex, being greater in girls compared to boys. These findings indicate the feasibility of this experimental induction of the startle reflex in response to predictable and unpredictable events in children and adolescents, enabling future research on inter-individual differences in fear and anxiety and their development in youth. PMID:21440905
Unpredictable Feeding Impairs Glucose Tolerance in Growing Lambs
Jaquiery, Anne L.; Oliver, Mark H.; Landon-Lane, Nina; Matthews, Samuel J.; Harding, Jane E.; Bloomfield, Frank H.
2013-01-01
Irregular eating is associated with insulin resistance and metabolic disease in adults but may affect young, growing children differently. We investigated the metabolic effects of unpredictable feeding in female juvenile lambs randomly assigned to receive, for six weeks, maintenance feed given twice daily in equal portions (Control Group, C; n = 24) or the same weekly feed amount in aliquots of variable size at unpredictable times (Unpredictable Group, U; n = 21). Intravenous glucose tolerance tests (IVGTT), insulin tolerance tests (ITT), and measurement of diurnal plasma cortisol concentrations were performed pre and post the dietary intervention. Groups were compared using t test and RM ANOVA. Weight gain was similar in both groups (C 18±2%; U 16±2% of initial body weight). Glucose area under the curve (AUC) was unchanged in C (AUC pre 818±34, post 801±33 mmol.min.l−1), but increased by 20% in U (pre 830±25, post 1010±19 mmol.min.l−1; p<0.0001), with an inadequate insulin response to glucose load (log(AUC insulin first 40 minutes) post intervention C 1.49±0.04 vs U 1.36±0.04 ng.min.ml−1; p = 0.03). Insulin tolerance and diurnal variation of plasma cortisol concentrations were not different between groups. Unpredictable feeding impairs insulin response to glucose in growing lambs despite high quality food and normal weight gain. Irregular eating warrants investigation as a potentially remediable risk factor for disordered glucose metabolism. PMID:23613779
Wu, Li-Min; Hu, Mei-Hong; Tong, Xian-Hong; Han, Hui; Shen, Ni; Jin, Ren-Tao; Wang, Wei; Zhou, Gui-Xiang; He, Guo-Ping; Liu, Yu-Sheng
2012-01-01
Brain-derived neurotropic factor (BDNF) was originally described in the nervous system but has been shown to be expressed in ovary tissues recently, acting as a paracrine/autocrine regulator required for developments of follicles and oocytes. Although it is generally accepted that chronic stress impairs female reproduction and decreases the expression of BDNF in limbic structures of central nervous system, which contributes to mood disorder. However, it is not known whether chronic stress affects oocytes developments, nor whether it affects expression of BDNF in ovary. Mice were randomly assigned into control group, stressed group, BDNF-treated group and BDNF-treated stressed group. The chronic unpredictable mild stress model was used to produce psychosocial stress in mice, and the model was verified by open field test and hypothalamic-pituitary-adrenal (HPA) axis activity. The methods of immunohistochemistry and western blotting were used to detect BDNF protein level and distribution. The number of retrieved oocytes, oocyte maturation, embryo cleavage and the rates of blastocyst formation after parthenogenetic activation were evaluated. Chronic unpredictable stress decreased the BDNF expression in antral follicles, but didn't affect the BDNF expression in primordial, primary and secondary follicles. Chronic unpredictable stress also decreased the number of retrieved oocytes and the rate of blastocyst formation, which was rescued by exogenous BDNF treatment. BDNF in mouse ovaries may be related to the decreased number of retrieved oocytes and impaired oocytes developmental potential induced by chronic unpredictable stress.
Tong, Xian-Hong; Han, Hui; Shen, Ni; Jin, Ren-Tao; Wang, Wei; Zhou, Gui-Xiang; He, Guo-Ping; Liu, Yu-Sheng
2012-01-01
Background Brain-derived neurotropic factor (BDNF) was originally described in the nervous system but has been shown to be expressed in ovary tissues recently, acting as a paracrine/autocrine regulator required for developments of follicles and oocytes. Although it is generally accepted that chronic stress impairs female reproduction and decreases the expression of BDNF in limbic structures of central nervous system, which contributes to mood disorder. However, it is not known whether chronic stress affects oocytes developments, nor whether it affects expression of BDNF in ovary. Methods Mice were randomly assigned into control group, stressed group, BDNF-treated group and BDNF-treated stressed group. The chronic unpredictable mild stress model was used to produce psychosocial stress in mice, and the model was verified by open field test and hypothalamic-pituitary-adrenal (HPA) axis activity. The methods of immunohistochemistry and western blotting were used to detect BDNF protein level and distribution. The number of retrieved oocytes, oocyte maturation, embryo cleavage and the rates of blastocyst formation after parthenogenetic activation were evaluated. Results Chronic unpredictable stress decreased the BDNF expression in antral follicles, but didn’t affect the BDNF expression in primordial, primary and secondary follicles. Chronic unpredictable stress also decreased the number of retrieved oocytes and the rate of blastocyst formation, which was rescued by exogenous BDNF treatment. Conclusion BDNF in mouse ovaries may be related to the decreased number of retrieved oocytes and impaired oocytes developmental potential induced by chronic unpredictable stress. PMID:23284991
Airs, R L; Temperton, B; Sambles, C; Farnham, G; Skill, S C; Llewellyn, C A
2014-10-16
We report production of chlorophyll f and chlorophyll d in the cyanobacterium Chlorogloeopsis fritschii cultured under near-infrared and natural light conditions. C. fritschii produced chlorophyll f and chlorophyll d when cultured under natural light to a high culture density in a 20 L bubble column photobioreactor. In the laboratory, the ratio of chlorophyll f to chlorophyll a changed from 1:15 under near-infrared, to an undetectable level of chlorophyll f under artificial white light. The results provide support that chlorophylls f and d are both red-light inducible chlorophylls in C. fritschii. Copyright © 2014 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
Otero, Carles; Aldaba, Mikel; López, Silvia; Díaz-Doutón, Fernando; Vera-Díaz, Fuensanta A; Pujol, Jaume
2018-06-01
To study the accommodative dynamics for predictable and unpredictable stimuli using manual and automated accommodative facility tests Materials and Methods: Seventeen young healthy subjects were tested monocularly in two consecutive sessions, using five different conditions. Two conditions replicated the conventional monocular accommodative facility tests for far and near distances, performed with manually held flippers. The other three conditions were automated and conducted using an electro-optical system and open-field autorefractor. Two of the three automated conditions replicated the predictable manual accommodative facility tests. The last automated condition was a hybrid approach using a novel method whereby far and near-accommodative-facility tests were randomly integrated into a single test of four unpredictable accommodative demands. The within-subject standard deviations for far- and near-distance-accommodative reversals were (±1,±1) cycles per minute (cpm) for the manual flipper accommodative facility conditions and (±3, ±4) cpm for the automated conditions. The 95% limits of agreement between the manual and the automated conditions for far and near distances were poor: (-18, 12) and (-15, 3). During the hybrid unpredictable condition, the response time and accommodative response parameters were significantly (p < 0.05) larger for accommodation than disaccommodation responses for high accommodative demands only. The response times during the transitions 0.17/2.17 D and 0.50/4.50 D appeared to be indistinguishable between the hybrid unpredictable and the conventional predictable automated tests. The automated accommodative facility test does not agree with the manual flipper test results. Operator delays in flipping the lens may account for these differences. This novel test, using unpredictable stimuli, provides a more comprehensive examination of accommodative dynamics than conventional manual accommodative facility tests. Unexpectedly, the unpredictability of the stimulus did not to affect accommodation dynamics. Further studies are needed to evaluate the sensitivity of this novel hybrid technique on individuals with accommodative anomalies.
Carod Artal, F J; Vázquez Cabrera, C B
The aim of this work was to study the cranial trepanations and deformations carried out by the ancient Paraca, Huari, Tiahuanaco and Inca cultures. To do so, we conducted a field study involving visits to archaeological remains and anthropological museums on the Andean plateau and the Peruvian coast. Cranial deformation was more common in the Andean regions and was performed by putting little pieces of wood or compressive bandages on newborn infants' heads in order to modify the growth axis of the cranial cavity. Cranial deformations were performed for aesthetic and magic religious reasons, but were also used as a means of ethnic or social identification, as a symbol of nobility or to distinguish the ruling classes. The immediate consequence of such deformation was the modification of the normal process by which the cranial sutures close. There is a significant correlation between the presence of posterior and lateral wormian bones, according to the degree of artificial deformation. The persistence of metopic suture and exostosis of the outer ear canal have been found in 5% of the skulls belonging to pre Columbine mummies. Other paleopathological findings include cranial fractures (7%), porotic hyperostosis (25% of children's skulls), spina bifida occulta, signs of spinal disk arthrosis and Pott's disease. Artificial cranial deformation was a very widespread practice in the Andean regions in pre Columbine times.
Arcoleo, Kimberly; Zayas, Luis E.; Hawthorne, April; Begay, Rachelle
2016-01-01
Objective Patients’ cultural health beliefs and behaviors may conflict with biomedical healthcare values and practices potentially leading to non-adherence with asthma treatment regimens. To optimize shared decision-making, healthcare providers should understand and be sensitive to these cultural beliefs and behaviors and negotiate an asthma management plan acceptable to parents. The purpose of this study was to obtain the perspective of Mexican mothers regarding (1) their experiences of living with a child with asthma, (2) their understanding of the nature of asthma, and (3) how their cultural beliefs influence asthma management. Methods A qualitative, phenomenological study design was employed to assess mothers’ lived experiences with and perceptions of their child’s asthma. Individual in-depth interviews were conducted with a purposeful sample of 20 Mexican mothers of children ages 5-17 years with asthma. An inductive, theory-driven, phenomenological analysis approach was used to elicit thematic findings. Results Mothers expressed a symptomatic perception of asthma and limited understanding of the disease. Most believe the disease is present only when their child is symptomatic. Many are surprised and puzzled by the unpredictability of their child’s asthma attacks, which they report as sometimes “silent”. The inconsistency of triggers also leads to frustration and worry, which may reflect their concerns around daily controller medication use and preference for alternative illness management strategies. Conclusions Our clinical encounters should be refocused to better understand the context of these families’ lives and the cultural lens through which they view their child’s asthma. PMID:25539396
Novel amelogenin-releasing hydrogel for remineralization of enamel artificial caries
Fan, Yuwei; Wen, Zezhang T; Liao, Sumei; Lallier, Thomas; Hagan, Joseph L; Twomley, Jefferson T; Zhang, Jian-Feng; Sun, Zhi; Xu, Xiaoming
2013-01-01
Recently, the use of recombinant full-length amelogenin protein in combination with fluoride has shown promising results in the formation of densely packed enamel-like structures. In this study, amelogenin (rP172)-releasing hydrogels containing calcium, phosphate, and fluoride were investigated for remineralization efficacy using in vitro early enamel caries models. The hydrogels were applied to artificial caries lesions on extracted human third molars, and the remineralization efficacy was tested in different models: static gel remineralization in the presence of artificial saliva, pH cyclic treatment at pH 5.4 acetic buffer and pH 7.3 gel remineralization, and treatment with multispecies oral biofilms grown in a continuous flowing constant-depth film fermenter. The surface microhardness of remineralized enamel increased significantly when amelogenin was released from hydrogel. No cytotoxicity was observed when periodontal ligament cells were cultured with the mineralized hydrogels. PMID:23338820
Molecular diversity of drinking water bacterial communities using 16S rRNA gene sequence analyses
Our understanding of the microbial community structure of drinking water distribution system has relied on culture-based methods. However, recent studies have suggested that the majority of bacteria inhabiting distribution systems are unable to grow on artificial media. The goal ...
Cryptococcus neoformans of Unusual Morphology
Cruickshank, J. G.; Cavill, R.; Jelbert, M.
1973-01-01
A case of primary cryptococcosis of the lungs was caused by an isolate of Cryptococcus neoformans that assumes a giant form in tissue but which has a normal appearance on artificial culture. Electron microscopy revealed gross enlargement of the capsule and plasma membranes in the tissue form. Images PMID:4121033
The description of microorganisms inhabiting drinking water distribution systems has commonly been performed using techniques that are biased towards easy to culture bacterial populations. As most environmental microorganisms cannot be grown on artificial media, our understanding...
NASA Astrophysics Data System (ADS)
Escalas, M.; Queralt, P.; Ledo, J.; Marcuello, A.
2012-04-01
Magnetotelluric (MT) method is a passive electromagnetic technique, which is currently used to characterize sites for the geological storage of CO2. These later ones are usually located nearby industrialized, urban or farming areas, where man-made electromagnetic (EM) signals contaminate the MT data. The identification and characterization of the artificial EM sources which generate the so-called "cultural noise" is an important challenge to obtain the most reliable results with the MT method. The polarization attributes of an EM signal (tilt angle, ellipticity and phase difference between its orthogonal components) are related to the character of its source. In a previous work (Escalas et al. 2011), we proposed a method to distinguish natural signal from cultural noise in the raw MT data. It is based on the polarization analysis of the MT time-series in the time-frequency domain, using a wavelet scheme. We developed an algorithm to implement the method, and was tested with both synthetic and field data. In 2010, we carried out a controlled-source electromagnetic (CSEM) experiment in the Hontomín site (the Research Laboratory on Geological Storage of CO2 in Spain). MT time-series were contaminated at different frequencies with the signal emitted by a controlled artificial EM source: two electric dipoles (1 km long, arranged in North-South and East-West directions). The analysis with our algorithm of the electric field time-series acquired in this experiment was successful: the polarization attributes of both the natural and artificial signal were obtained in the time-frequency domain, highlighting their differences. The processing of the magnetic field time-series acquired in the Hontomín experiment has been done in the present work. This new analysis of the polarization attributes of the magnetic field data has provided additional information to detect the contribution of the artificial source in the measured data. Moreover, the joint analysis of the polarization attributes of the electric and magnetic field has been crucial to fully characterize the properties and the location of the noise source. Escalas, M., Queralt, P., Ledo, J., Marcuello, A., 2011. Identification of cultural noise sources in magnetotelluric data: estimating polarization attributes in the time-frequency domain using wavelet analysis. Geophysical Research Abstracts Vol. 13, EGU2011-6085. EGU General Assembly 2011.
ERIC Educational Resources Information Center
Meulders, Ann; Vervliet, Bram; Vansteenwegen, Debora; Hermans, Dirk; Baeyens, Frank
2011-01-01
Unpredictability of an unconditioned stimulus (US) typically produces context conditioning in animals and humans. We modified the Martians task--a computer game measuring learning of Pavlovian associations through conditioned suppression--for assessing context conditioning in humans. One between-subjects and one within-subjects study are reported.…
Natural language from artificial life.
Kirby, Simon
2002-01-01
This article aims to show that linguistics, in particular the study of the lexico-syntactic aspects of language, provides fertile ground for artificial life modeling. A survey of the models that have been developed over the last decade and a half is presented to demonstrate that ALife techniques have a lot to offer an explanatory theory of language. It is argued that this is because much of the structure of language is determined by the interaction of three complex adaptive systems: learning, culture, and biological evolution. Computational simulation, informed by theoretical linguistics, is an appropriate response to the challenge of explaining real linguistic data in terms of the processes that underpin human language.
S. sanguinis adhesion on rough titanium surfaces: effect of culture media.
Rodríguez-Hernández, Ana G; Muñoz-Tabares, José A; Godoy-Gallardo, Maria; Juárez, Antonio; Gil, Francisco-Javier
2013-03-01
Bacterial colonization plays a key role in dental implant failure, because they attach directly on implant surface upon implantation. Between different types of bacteria associated with the oral environment, Streptococcus sanguinis is essential in this process since it is an early colonizer. In this work the relationship between titanium surfaces modified by shot blasting treatment and S. sanguinis adhesion; have been studied in approached human mouth environment. Bacteria pre-inoculated with routinary solution were put in contact with titanium samples, shot-blasted with alumina and silicon carbide, and adhesion results were compared with those obtained when bacteria were pre-inoculated with modified artificial saliva medium and on saliva pre-coated titanium samples. Our results showed that bacterial adhesion on titanium samples was influenced by culture conditions. When S. sanguinis was inoculated in routinary culture media, colonies forming unities per square millimeter presented an increment correlated with roughness and surface energy, but separated by the type of particle used during shot-blasting treatment; whereas in modified artificial saliva only a relationship between bacteria adhered and the increment in both roughness and surface energy were observed, regardless of the particle type. Finally, on human saliva pre-coated samples no significant differences were observed among roughness, surface energy or particle. Copyright © 2012 Elsevier B.V. All rights reserved.
Lipid production of Chlorella vulgaris cultured in artificial wastewater medium.
Feng, Yujie; Li, Chao; Zhang, Dawei
2011-01-01
Chlorella vulgaris was used to study algal lipid production with wastewater treatment. Artificial wastewater was used to cultivate C. vulgaris in a column aeration photobioreactor (CAP) under batch and semi-continuous cultivation with various daily culture replacements (0.5l-1.5l per 2l reactor). The cell density was decreased from 0.89 g/l with the daily replacement of 0.5l to 0.28 g/l with 1.5l replacement. However, C. vulgaris culture achieved the highest lipid content (42%, average value of the phase) and the lipid productivity (147 mg/ld(-1)) with daily replacement of 1.0 l. And then the nutrient removal efficiency were 86% (COD), 97% (NH(4)(+)) and 96% (TP), respectively. Analyses of energy efficiency showed that the net energy ratio (NER) for lipid production with daily replacement of 1.0 l (1.25) was higher than the other volume replacement protocols. And cost analyses showed that the algal biomass can be competitive with petroleum at US$ 63.97 per barrel with the potential credit for wastewater treatment. According to the above results, it is concluded that the present research will lead to an economical technology of algal lipid production. Copyright © 2010 Elsevier Ltd. All rights reserved.
Mahoney, Mark M.; Staley, Kevin J.
2017-01-01
Rodent organotypic hippocampal cultures spontaneously develop epileptiform activity after approximately 2 weeks in vitro and are increasingly used as a model of chronic post-traumatic epilepsy. However, organotypic cultures are maintained in an artificial environment (culture medium), which contains electrolytes, glucose, amino acids and other components that are not present at the same concentrations in cerebrospinal fluid (CSF). Therefore, it is possible that epileptogenesis in organotypic cultures is driven by these components. We examined the influence of medium composition on epileptogenesis. Epileptogenesis was evaluated by measurements of lactate and lactate dehydrogenase (LDH) levels (biomarkers of ictal activity and cell death, respectively) in spent culture media, immunohistochemistry and automated 3-D cell counts, and extracellular recordings from CA3 regions. Changes in culture medium components moderately influenced lactate and LDH levels as well as electrographic seizure burden and cell death. However, epileptogenesis occurred in any culture medium that was capable of supporting neural survival. We conclude that medium composition is unlikely to be the cause of epileptogenesis in the organotypic hippocampal culture model of chronic post-traumatic epilepsy. PMID:28225808
Liu, Jing; Saponjian, Yero; Mahoney, Mark M; Staley, Kevin J; Berdichevsky, Yevgeny
2017-01-01
Rodent organotypic hippocampal cultures spontaneously develop epileptiform activity after approximately 2 weeks in vitro and are increasingly used as a model of chronic post-traumatic epilepsy. However, organotypic cultures are maintained in an artificial environment (culture medium), which contains electrolytes, glucose, amino acids and other components that are not present at the same concentrations in cerebrospinal fluid (CSF). Therefore, it is possible that epileptogenesis in organotypic cultures is driven by these components. We examined the influence of medium composition on epileptogenesis. Epileptogenesis was evaluated by measurements of lactate and lactate dehydrogenase (LDH) levels (biomarkers of ictal activity and cell death, respectively) in spent culture media, immunohistochemistry and automated 3-D cell counts, and extracellular recordings from CA3 regions. Changes in culture medium components moderately influenced lactate and LDH levels as well as electrographic seizure burden and cell death. However, epileptogenesis occurred in any culture medium that was capable of supporting neural survival. We conclude that medium composition is unlikely to be the cause of epileptogenesis in the organotypic hippocampal culture model of chronic post-traumatic epilepsy.
Socio-Cultural Imbalances in AIED Research: Investigations, Implications and Opportunities
ERIC Educational Resources Information Center
Blanchard, Emmanuel G.
2015-01-01
This paper investigates international representations in the Artificial Intelligence in Education (AIED) research field. Its methodological and theoretical groundings are inspired by Arnett (2008) and Henrich et al. (2010a) who addressed the same issue in psychology, and respectively a) discovered massive imbalances in representation in top-tier…
Computational Models for Belief Revision, Group Decision-Making and Cultural Shifts
2010-10-25
34social" networks; the green numbers are pseudo-trees or artificial (non-social) constructions. The dashed blue line indicates the range of Erdos- Renyi ...non-social networks such as Erdos- Renyi random graphs or the more passive non-cognitive spreading of disease or information flow, As mentioned
Studies suggest that periphyton in streambeds can harbor fecal indicator bacteria (FIB) and, under certain circumstances, can be transferred from the periphyton biofilm into the surface water. An indoor mesocosm study was conducted at the U.S. Environmental Protection Agency Expe...
Computers and Classroom Culture.
ERIC Educational Resources Information Center
Schofield, Janet Ward
This book explores the meaning of computer technology in schools. The book is based on data gathered from a two-year observation of more than 30 different classrooms in an urban high school: geometry classes in which students used artificially intelligent tutors; business classes in which students learned word processing; and computer science…
Striatal dopamine transmission in healthy humans during a passive monetary reward task.
Hakyemez, Hélène S; Dagher, Alain; Smith, Stephen D; Zald, David H
2008-02-15
Research on dopamine (DA) transmission has emphasized the importance of increased phasic DA cell firing in the presence of unpredictable rewards. Using [(11)C]raclopride PET, we previously reported that DA transmission was both suppressed and enhanced in different regions of the striatum during an unpredictable reward task [Zald, D.H., Boileau, I., El Dearedy, W., Gunn, R., McGlone, F., Dichter, G.S. et al. (2004). Dopamine transmission in the human striatum during monetary reward tasks. J. Neurosci. 24, 4105-4112]. However, it was unclear if reductions in DA release during this task reflected a response to the high proportion of nonrewarding trials, and whether the behavioral demands of the task influenced the observed response. To test these issues, we presented 10 healthy subjects with an automated (passive) roulette wheel game in which the amount of reward and its timing were unpredictable and the rewarding trials greatly outnumbered the nonrewarding ones. As in the previous study, DA transmission in the putamen was significantly suppressed relative to a predictable control condition. A similar suppression occurred when subjects were presented with temporally unpredictable novel pictures and sounds. At present, models of DA functioning during reward do not account for this suppression, but given that it has been observed in two different studies using different reward paradigms, this phenomenon warrants attention. Neither the unpredictable reward nor the novelty conditions produced consistent increases in striatal DA transmission. These data suggest that active behavioral engagement may be necessary to observe robust statewise increases in DA release in the striatum.
Chaloner, Aaron; Greenwood-Van Meerveld, Beverley
2013-03-01
Visceral pain is the hallmark feature of irritable bowel syndrome (IBS), a gastrointestinal disorder, which is more commonly diagnosed in women. Female IBS patients frequently report a history of early life adversity (ELA); however, sex differences in ELA-induced visceral pain and the role of ovarian hormones have yet to be investigated. Therefore, we tested the hypothesis that ELA induces visceral hypersensitivity through a sexually dimorphic mechanism mediated via estradiol. As a model of ELA, neonatal rats were exposed to different pairings of an odor and shock to control for trauma predictability. In adulthood, visceral sensitivity was assessed via a visceromotor response to colorectal distension. Following ovariectomy and estradiol replacement in a separate group of rats, the visceral sensitivity was quantified. We found that females that received unpredictable odor-shock developed visceral hypersensitivity in adulthood. In contrast, visceral sensitivity was not significantly different following ELA in adult males. Ovariectomy reversed visceral hypersensitivity following unpredictable ELA, whereas estradiol replacement reestablished visceral hypersensitivity in the unpredictable group. This study is the first to show sex-related differences in visceral sensitivity following unpredictable ELA. Our data highlight the activational effect of estradiol as a pivotal mechanism in maintaining visceral hypersensitivity. This article directly implicates a critical role for ovarian hormones in maintaining visceral hypersensitivity following ELA, specifically identifying the activational effect of estradiol as a key modulator of visceral sensitivity. These data suggest that ELA induces persistent functional abdominal pain in female IBS patients through an estrogen-dependent mechanism. Copyright © 2013 American Pain Society. All rights reserved.
Lee, Wonseok; Bae, Hyoung Won; Lee, Si Hyung; Kim, Chan Yun; Seong, Gong Je
2017-03-01
To assess the accuracy of intraocular lens (IOL) power prediction for cataract surgery with open angle glaucoma (OAG) and to identify preoperative angle parameters correlated with postoperative unpredicted refractive errors. This study comprised 45 eyes from 45 OAG subjects and 63 eyes from 63 non-glaucomatous cataract subjects (controls). We investigated differences in preoperative predicted refractive errors and postoperative refractive errors for each group. Preoperative predicted refractive errors were obtained by biometry (IOL-master) and compared to postoperative refractive errors measured by auto-refractometer 2 months postoperatively. Anterior angle parameters were determined using swept source optical coherence tomography. We investigated correlations between preoperative angle parameters [angle open distance (AOD); trabecular iris surface area (TISA); angle recess area (ARA); trabecular iris angle (TIA)] and postoperative unpredicted refractive errors. In patients with OAG, significant differences were noted between preoperative predicted and postoperative real refractive errors, with more myopia than predicted. No significant differences were recorded in controls. Angle parameters (AOD, ARA, TISA, and TIA) at the superior and inferior quadrant were significantly correlated with differences between predicted and postoperative refractive errors in OAG patients (-0.321 to -0.408, p<0.05). Superior quadrant AOD 500 was significantly correlated with postoperative refractive differences in multivariate linear regression analysis (β=-2.925, R²=0.404). Clinically unpredicted refractive errors after cataract surgery were more common in OAG than in controls. Certain preoperative angle parameters, especially AOD 500 at the superior quadrant, were significantly correlated with these unpredicted errors.
Lee, Wonseok; Bae, Hyoung Won; Lee, Si Hyung; Kim, Chan Yun
2017-01-01
Purpose To assess the accuracy of intraocular lens (IOL) power prediction for cataract surgery with open angle glaucoma (OAG) and to identify preoperative angle parameters correlated with postoperative unpredicted refractive errors. Materials and Methods This study comprised 45 eyes from 45 OAG subjects and 63 eyes from 63 non-glaucomatous cataract subjects (controls). We investigated differences in preoperative predicted refractive errors and postoperative refractive errors for each group. Preoperative predicted refractive errors were obtained by biometry (IOL-master) and compared to postoperative refractive errors measured by auto-refractometer 2 months postoperatively. Anterior angle parameters were determined using swept source optical coherence tomography. We investigated correlations between preoperative angle parameters [angle open distance (AOD); trabecular iris surface area (TISA); angle recess area (ARA); trabecular iris angle (TIA)] and postoperative unpredicted refractive errors. Results In patients with OAG, significant differences were noted between preoperative predicted and postoperative real refractive errors, with more myopia than predicted. No significant differences were recorded in controls. Angle parameters (AOD, ARA, TISA, and TIA) at the superior and inferior quadrant were significantly correlated with differences between predicted and postoperative refractive errors in OAG patients (-0.321 to -0.408, p<0.05). Superior quadrant AOD 500 was significantly correlated with postoperative refractive differences in multivariate linear regression analysis (β=-2.925, R2=0.404). Conclusion Clinically unpredicted refractive errors after cataract surgery were more common in OAG than in controls. Certain preoperative angle parameters, especially AOD 500 at the superior quadrant, were significantly correlated with these unpredicted errors. PMID:28120576
Complexity in Dynamical Systems
NASA Astrophysics Data System (ADS)
Moore, Cristopher David
The study of chaos has shown us that deterministic systems can have a kind of unpredictability, based on a limited knowledge of their initial conditions; after a finite time, the motion appears essentially random. This observation has inspired a general interest in the subject of unpredictability, and more generally, complexity; how can we characterize how "complex" a dynamical system is?. In this thesis, we attempt to answer this question with a paradigm of complexity that comes from computer science, we extract sets of symbol sequences, or languages, from a dynamical system using standard methods of symbolic dynamics; we then ask what kinds of grammars or automata are needed a generate these languages. This places them in the Chomsky heirarchy, which in turn tells us something about how subtle and complex the dynamical system's behavior is. This gives us insight into the question of unpredictability, since these automata can also be thought of as computers attempting to predict the system. In the culmination of the thesis, we find a class of smooth, two-dimensional maps which are equivalent to the highest class in the Chomsky heirarchy, the turning machine; they are capable of universal computation. Therefore, these systems possess a kind of unpredictability qualitatively different from the usual "chaos": even if the initial conditions are known exactly, questions about the system's long-term dynamics are undecidable. No algorithm exists to answer them. Although this kind of unpredictability has been discussed in the context of distributed, many-degree-of -freedom systems (for instance, cellular automata) we believe this is the first example of such phenomena in a smooth, finite-degree-of-freedom system.
Hui, Jiaojie; Zhang, Jianping; Pu, Mengjia; Zhou, Xingliang; Dong, Liang; Mao, Xuqiang; Shi, Guofeng; Zou, Jian; Wu, Jingjing; Jiang, Dongmei; Xi, Guangjun
2018-04-23
It is widely accepted that cognitive processes, such as learning and memory, are affected in depression, but the molecular mechanisms underlying the interactions of these 2 disorders are not clearly understood. Recently, glycogen synthase kinase-3 beta (GSK-3β)/β-catenin signaling was shown to play an important role in the regulation of learning and memory. The present study used a rat model of depression, chronic unpredictable stress, to determine whether hippocampal GSK-3β/β-catenin signaling was involved in learning and memory alterations. Our results demonstrated that chronic unpredictable stress had a dramatic influence on spatial cognitive performance in the Morris water maze task and reduced the phosphorylation of Ser9 of GSK-3β as well as the total and nuclear levels of β-catenin in the hippocampus. Inhibition of GSK3β by SB216763 significantly ameliorated the cognitive deficits induced by chronic unpredictable stress, while overexpression of GSK3β by AAV-mediated gene transfer significantly decreased cognitive performance in adult rats. In addition, chronic unpredictable stress exposure increased the expression of the canonical Wnt antagonist Dkk-1. Furthermore, chronic administration of corticosterone significantly increased Dkk-1 expression, decreased the phosphorylation of Ser9 of GSK-3β, and resulted in the impairment of hippocampal learning and memory. Our results indicate that impairment of learning and memory in response to chronic unpredictable stress may be attributed to the dysfunction of GSK-3β/β-catenin signaling mediated by increased glucocorticoid signaling via Dkk-1.
ERIC Educational Resources Information Center
Simpson, Jeffry A.; Griskevicius, Vladas; Kuo, Sally I-Chun; Sung, Sooyeon; Collins, W. Andrew
2012-01-01
According to a recent evolutionary life history model of development proposed by Ellis, Figueredo, Brumbach, and Schlomer (2009), growing up in harsh versus unpredictable environments should have unique effects on life history strategies in adulthood. Using data from the Minnesota Longitudinal Study of Risk and Adaptation, we tested how harshness…
NASA Astrophysics Data System (ADS)
Munn, Adam J.; Kern, Pippa; McAllan, Bronwyn M.
2010-06-01
The severity, duration and amplitude of extreme weather events are forecast to intensify with current climate trends, over both long (e.g. seasonal) and short (e.g. daily) time-scales. As such, the predictability of food supplies for many small endotherms is likely to become increasingly important. Numerous small mammals and birds combat food shortages using torpor, a controlled reduction in metabolic rate and body temperature that helps lower their daily energy requirements. As such, torpor often has been cited as a key feature allowing some small endotherms to survive highly unpredictable climates, such as tropics or dry deserts, but mensurative demonstrations of this are lacking. We have shown here that when a small desert marsupial, the fat-tailed dunnart ( Sminthopsis crassicaudata), is offered unpredictable levels of daily food, they increase frequency of daily torpor and length of bouts compared with animals offered ad libitum food, but this was not found for animals offered a 70% food-restricted diet. Our data suggest that simple food restriction may not be sufficient for evaluating the efficacy of torpor as a strategy for managing unpredictable climates.
NASA Astrophysics Data System (ADS)
Ohtomo, Y.; Ijiri, A.; Ikegawa, Y.; Tsutsumi, M.; Imachi, H.; Uramoto, G.; Hoshino, T.; Morono, Y.; Tanikawa, W.; Hirose, T.; Inagaki, F.
2013-12-01
The geological CO2 sequestration into subsurface unmineable oil/gas fields and coal formations has been considered as one of the possible ways to reduce dispersal of anthropogenic greenhouse gasses into the atmosphere. However, feasibility of CO2 injection largely depends on a variety of geological and economical settings, and its ecological consequences have remained largely unpredictable. To address these issues, we developed a new flow-through-type CO2 injection system designated as the 'geobio-reactor system' to examine possible geophysical, geochemical and microbiological impact caused by CO2 injection under in-situ pressure (0-100 MPa) and temperature (0-70°C) conditions. In this study, we investigated Eocene bituminous coal-sandstones in the northwestern Pacific coast, Hokkaido, Japan, using the geobio-reactor system. Anaerobic artificial fluid and CO2 (flow rate: 0.002 and 0.00001 mL/min, respectively) were continuously supplemented into the coal-sand column under the pore pressure of 40 MPa (confined pressure: 41 MPa) at 40°C for 56 days. Molecular analysis of bacterial 16S rRNA genes showed that predominant bacterial components were physically dispersed from coal to sand as the intact form during experiment. Cultivation experiments from sub-sampling fluids indicated that some terrestrial microbes could preserve their survival in subsurface condition. Molecular analysis of archaeal 16S rRNA genes also showed that no methanogens were activated during experiment. We also anaerobically incubated the coal sample using conventional batch-type cultivation technique with a medium for methanogens. After one year of the batch incubation at 20°C, methane could be detected from the cultures except for the acetate-fed culture. The sequence of archaeal 16S rRNA genes via PCR amplification obtained from the H2 plus formate-fed culture was affiliated with a hydrogenotrophic methanogen within the genus Methanobacterium, whereas the methanol plus trimethylamine culture belonged to a methylotrophic methanogen within the genus Methanosarcina. For the acetate-fed culture, no cell proliferation and methane-production were observed after two-years incubation. During the injection of CO2 and fluid, increase of dissolved CH4 concentration was observed, of which δ13CCH4 were constantly similar to those of the absorbed coal-bed methane (δ13CCBM, ~70‰), suggesting the enhanced gas recovery with fluid flow. The output volume of CO2 (ΣCO2out, 22.1 to 125.6 mM) was smaller than initial concentration (ΣCO2in, 138.38 mM), which can be explained by either adsorption on coal, formation of carbonate minerals, or microbial consumption. Increase of acetate concentration in the fluids was also observed, whereas δ13Cacetate depleted during experiment. Considering with the decrease of additive H2, it is most likely that homo-acetogenesis would occur during experiments, which is consistent with detection of Sporomusa-related 16S rRNA genes, homo-acetogenic bacterium, in cloning analysis of sandstone after experiment. Decrease of formate concentrations and increase of δ13Cformate indicate bacterial consumption of formate and isotopic fractionation. Our results suggest that CO2 injection to natural coal-sand formation stimulates homo-acetogenesis rather than methanogenesis, accompanied by biogenic CO2 conversion to acetate.
Is in-group bias culture-dependent? A meta-analysis across 18 societies.
Fischer, Ronald; Derham, Crysta
2016-01-01
We report a meta-analysis on the relationship between in-group bias and culture. Our focus is on whether broad macro-contextual variables influence the extent to which individuals favour their in-group. Data from 21,266 participants from 18 societies included in experimental and survey studies were available. Using Hofstede's (1980) and Schwartz (2006) culture-level predictors in a 3-level mixed-effects meta-analysis, we found strong support for the uncertainty-reduction hypothesis. An interaction between Autonomy and real vs artificial groups suggested that in low autonomy contexts, individuals show greater in-group bias for real groups. Implications for social identity theory and intergroup conflict are outlined.
NASA Astrophysics Data System (ADS)
Mirsafianf, Atefeh S.; Isfahani, Shirin N.; Kasaei, Shohreh; Mobasheri, Hamid
Here we present an approach for processing neural cells images to analyze their growth process in culture environment. We have applied several image processing techniques for: 1- Environmental noise reduction, 2- Neural cells segmentation, 3- Neural cells classification based on their dendrites' growth conditions, and 4- neurons' features Extraction and measurement (e.g., like cell body area, number of dendrites, axon's length, and so on). Due to the large amount of noise in the images, we have used feed forward artificial neural networks to detect edges more precisely.
Optical properties of an anterior lamellar human cornea model based on fibrin-agarose
NASA Astrophysics Data System (ADS)
Ionescu, Ana M.; Cardona, Juan de la Cruz; Ghinea, Razvan; Garzón, Ingrid; González-Andrades, Miguel; Alaminos, Miguel; Pérez, Maria del Mar
2017-08-01
The optical evaluation carried out using the Inverse Adding-Doubling (IAD) method to determine the scattering and the absorption coefficients of the bioengineered human corneal stromas showed that this type of artificial biomaterials shared many similarities with native control cornea after four weeks of development in culture. Their absorption and reduced scattering coefficients values were higher than the ones of the control cornea, but their spectral behaviors of both coefficients were similar. Time of development in culture was an influencing factor on the results.
Development of Fundamental Technologies for Micro Bioreactors
NASA Astrophysics Data System (ADS)
Sato, Kiichi; Kitamori, Takehiko
This chapter reviews the development of fundamental technologies required for microchip-based bioreactors utilizing living mammalian cells and pressure driven flow. The most important factor in the bioreactor is the cell culture. For proper cell culturing, continuous medium supply from a microfluidic channel and appropriate modification of the channel surface to accommodate cell attachment is required. Moreover, the medium flow rate should be chosen carefully, because shear stress affects cell activity. The techniques presented here could be applied to the development of micro bioreactors such as microlivers, pigment production by plant cells, and artificial insemination.
Hagihara, Yoshihisa; Mine, Shouhei; Uegaki, Koichi
2007-12-14
We report for the first time the stabilization of an immunoglobulin fold domain by an engineered disulfide bond. In the llama single-domain antibody, which has human chorionic gonadotropin as its specific antigen, Ala49 and Ile70 are buried in the structure. A mutant with an artificial disulfide bond at this position showed a 10 degrees C higher midpoint temperature of thermal unfolding than that without the extra disulfide bond. The modified domains exhibited an antigen binding affinity comparable with that of the wild-type domain. Ala49 and Ile70 are conserved in camel and llama single-domain antibody frameworks. Therefore, domains against different antigens are expected to be stabilized by the engineered disulfide bond examined here. In addition to the effect of the loop constraints in the unfolded state, thermodynamic analysis indicated that internal interaction and hydration also control the stability of domains with disulfide bonds. The change in physical properties resulting from mutation often causes unpredictable and destabilizing effects on these interactions. The introduction of a hydrophobic cystine into the hydrophobic region maintains the hydrophobicity of the protein and is expected to minimize the unfavorable mutational effects.
A vision-based system for fast and accurate laser scanning in robot-assisted phonomicrosurgery.
Dagnino, Giulio; Mattos, Leonardo S; Caldwell, Darwin G
2015-02-01
Surgical quality in phonomicrosurgery can be improved by open-loop laser control (e.g., high-speed scanning capabilities) with a robust and accurate closed-loop visual servoing systems. A new vision-based system for laser scanning control during robot-assisted phonomicrosurgery was developed and tested. Laser scanning was accomplished with a dual control strategy, which adds a vision-based trajectory correction phase to a fast open-loop laser controller. The system is designed to eliminate open-loop aiming errors caused by system calibration limitations and by the unpredictable topology of real targets. Evaluation of the new system was performed using CO(2) laser cutting trials on artificial targets and ex-vivo tissue. This system produced accuracy values corresponding to pixel resolution even when smoke created by the laser-target interaction clutters the camera view. In realistic test scenarios, trajectory following RMS errors were reduced by almost 80 % with respect to open-loop system performances, reaching mean error values around 30 μ m and maximum observed errors in the order of 60 μ m. A new vision-based laser microsurgical control system was shown to be effective and promising with significant positive potential impact on the safety and quality of laser microsurgeries.
Seawater-cultured Botryococcus braunii for efficient hydrocarbon extraction.
Furuhashi, Kenichi; Saga, Kiyotaka; Okada, Shigeru; Imou, Kenji
2013-01-01
As a potential source of biofuel, the green colonial microalga Botryococcus braunii produces large amounts of hydrocarbons that are accumulated in the extracellular matrix. Generally, pretreatment such as drying or heating of wet algae is needed for sufficient recoveries of hydrocarbons from B. braunii using organic solvents. In this study, the Showa strain of B. braunii was cultured in media derived from the modified Chu13 medium by supplying artificial seawater, natural seawater, or NaCl. After a certain period of culture in the media with an osmotic pressure corresponding to 1/4-seawater, hydrocarbon recovery rates exceeding 90% were obtained by simply mixing intact wet algae with n-hexane without any pretreatments and the results using the present culture conditions indicate the potential for hydrocarbon milking. Seawater was used for efficient hydrocarbon extraction from Botryococcus braunii. The alga was cultured in media prepared with seawater or NaCl. Hydrocarbon recovery rate exceeding 90% was obtained without any pretreatment.
Geng, Li; Qiao, Guang-yan; Gu, Kai-ka
2016-04-01
To investigate the effect of fluoride on electrochemical corrosion of the dental pure titanium before and after adhesion of Streptococcus mutans. The dental pure titanium specimens were tested by electrochemical measurement system including electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization curve (PD) methods in artificial saliva with 0 g/L and 1.0 g/L sodium fluoride before and after dipped into culture medium with Streptococcus mutans for 24 h. The corrosion parameters, including the polarization resistance (R(ct)), corrosion potential (E(corr)), pitting breakdown potential (E(b)), and the difference between E(corr) and E(b) representing the "pseudo-passivation" (ΔE) obtained from the electrochemical tests were used to evaluate the corrosion resistance of dental pure titanium. The data were statistically analyzed by 2×2 factorial statistical analysis to examine the effect of sodium fluoride and adhesion of Streptococcus mutans using SPSS 12.0 software package. The results showed that the corrosion parameters including R(ct), Ecorr, E(b), and ΔE of pure titanium had significant difference between before and after adhesion of Streptococcus mutans in the same solution(P<0.05), and in artificial saliva with 0 g/L and 1.0 g/L sodium fluoride(P<0.05). The dental pure titanium was prone to corrosion in artificial saliva with sodium fluoride. The corrosion resistance of pure titanium decreased distinctly after immersed in culture medium with Streptococcus mutans.
Highly stable maintenance of a mouse artificial chromosome in human cells and mice.
Kazuki, Kanako; Takehara, Shoko; Uno, Narumi; Imaoka, Natsuko; Abe, Satoshi; Takiguchi, Masato; Hiramatsu, Kei; Oshimura, Mitsuo; Kazuki, Yasuhiro
2013-12-06
Human artificial chromosomes (HACs) and mouse artificial chromosomes (MACs) display several advantages as gene delivery vectors, such as stable episomal maintenance that avoids insertional mutations and the ability to carry large gene inserts including the regulatory elements. Previously, we showed that a MAC vector developed from a natural mouse chromosome by chromosome engineering was more stably maintained in adult tissues and hematopoietic cells in mice than HAC vectors. In this study, to expand the utility for a gene delivery vector in human cells and mice, we investigated the long-term stability of the MACs in cultured human cells and transchromosomic mice. We also investigated the chromosomal copy number-dependent expression of genes on the MACs in mice. The MAC was stably maintained in human HT1080 cells in vitro during long-term culture. The MAC was stably maintained at least to the F8 and F4 generations in ICR and C57BL/6 backgrounds, respectively. The MAC was also stably maintained in hematopoietic cells and tissues derived from old mice. Transchromosomic mice containing two or four copies of the MAC were generated by breeding. The DNA contents were comparable to the copy number of the MACs in each tissue examined, and the expression of the EGFP gene on the MAC was dependent on the chromosomal copy number. Therefore, the MAC vector may be useful not only for gene delivery in mammalian cells but also for animal transgenesis. Copyright © 2013 Elsevier Inc. All rights reserved.
Box 11: Tissue Engineering and Bioscience Methods Using Proton Beam Writing
NASA Astrophysics Data System (ADS)
van Kan, J. A.
Tissue engineering is a rapidly developing and highly interdisciplinary field that applies the principles of cell biology, engineering, and materials science to the culture of biological tissue. The artificially grown tissue then can be implanted directly into the body, or it can form part of a device that replaces organ functionality.
Teaching Foreign Languages with Realia and Other Authentic Materials. ERIC Q&A.
ERIC Educational Resources Information Center
Berwald, Jean-Pierre
Realia, authentic documents, and mass media are living daily proof of the value of language. Their authenticity, specialized vocabulary, reinforced grammatical structures, and topics of interest can help encourage interest in the target language and culture. They contain current language on all imaginable topics, and are not artificial or…
Saunders, Timothy J; Taylor, Alex H; Atkinson, Quentin D
2016-10-01
Monitoring cues, such as an image of a face or pair of eyes, have been found to increase prosocial behaviour in several studies. However, other studies have found little or no support for this effect. Here, we examined whether monitoring cues affect online donations to charity while manipulating the emotion displayed, the number of watchers and the cue type. We also include as statistical controls a range of likely covariates of prosocial behaviour. Using the crowdsourcing Internet marketplace, Amazon Mechanical Turk (MTurk), 1535 participants completed our survey and were given the opportunity to donate to charity while being shown an image prime. None of the monitoring primes we tested had a significant effect on charitable giving. By contrast, the control variables of culture, age, sex and previous charity giving frequency did predict donations. This work supports the importance of cultural differences and enduring individual differences in prosocial behaviour and shows that a range of artificial monitoring cues do not reliably boost online charity donation on MTurk.
Park, Keun-Hong; Bae, You Han
2002-07-01
The spheroid of specific cells is often regarded as the better form in artificial organs and mammalian cell bioreactors for improved cell-specific functions. In this study, freshly harvested primary rat hepatocytes, which had been cultivated as spheroids and entrapped in a synthetic thermo-reversible extracellular matrix, were examined for differentiated morphology and enhanced liver-specific functions as compared to a control set (hepatocytes in single-cell form). A copolymer of N-isopropylacrylamide (98 mole % in the feed) and acrylic acid (poly(NiPAAm-co-AAc)), and the adhesion molecule, an Arg-Gly-Asp (RGD)-incorporated thermo-reversible matrix, were used to entrap hepatocytes in the form of either spheroids or single cells. In a 28-day culture period, the spheroids in the RGD-incorporated gel maintained higher viability and produced albumin and urea at constant rates, while there was lower cell viability and less albumin secretion by the spheroids in p(NiPAAm-co-AAc). Hepatocytes cultured as spheroids in the RGD-incorporated gel would constitute a potentially useful three-dimensional cell system for application in a bio-artificial liver device.
Saunders, Timothy J.; Atkinson, Quentin D.
2016-01-01
Monitoring cues, such as an image of a face or pair of eyes, have been found to increase prosocial behaviour in several studies. However, other studies have found little or no support for this effect. Here, we examined whether monitoring cues affect online donations to charity while manipulating the emotion displayed, the number of watchers and the cue type. We also include as statistical controls a range of likely covariates of prosocial behaviour. Using the crowdsourcing Internet marketplace, Amazon Mechanical Turk (MTurk), 1535 participants completed our survey and were given the opportunity to donate to charity while being shown an image prime. None of the monitoring primes we tested had a significant effect on charitable giving. By contrast, the control variables of culture, age, sex and previous charity giving frequency did predict donations. This work supports the importance of cultural differences and enduring individual differences in prosocial behaviour and shows that a range of artificial monitoring cues do not reliably boost online charity donation on MTurk. PMID:27853533
Electrospinning of Biocompatible Nanofibers
NASA Astrophysics Data System (ADS)
Coughlin, Andrew J.; Queen, Hailey A.; McCullen, Seth D.; Krause, Wendy E.
2006-03-01
Artificial scaffolds for growing cells can have a wide range of applications including wound coverings, supports in tissue cultures, drug delivery, and organ and tissue transplantation. Tissue engineering is a promising field which may resolve current problems with transplantation, such as rejection by the immune system and scarcity of donors. One approach to tissue engineering utilizes a biodegradable scaffold onto which cells are seeded and cultured, and ideally develop into functional tissue. The scaffold acts as an artificial extracellular matrix (ECM). Because a typical ECM contains collagen fibers with diameters of 50-500 nm, electrostatic spinning (electrospinning) was used to mimic the size and structure of these fibers. Electrospinning is a novel way of spinning a nonwoven web of fibers on the order of 100 nm, much like the web of collagen in an ECM. We are investigating the ability of several biocompatible polymers (e.g., chitosan and polyvinyl alcohol) to form defect-free nanofiber webs and are studying the influence of the zero shear rate viscosity, molecular weight, entanglement concentration, relaxation time, and solvent on the resulting fiber size and morphology.
Biomedical engineering for health research and development.
Zhang, X-Y
2015-01-01
Biomedical engineering is a new area of research in medicine and biology, providing new concepts and designs for the diagnosis, treatment and prevention of various diseases. There are several types of biomedical engineering, such as tissue, genetic, neural and stem cells, as well as chemical and clinical engineering for health care. Many electronic and magnetic methods and equipments are used for the biomedical engineering such as Computed Tomography (CT) scans, Magnetic Resonance Imaging (MRI) scans, Electroencephalography (EEG), Ultrasound and regenerative medicine and stem cell cultures, preparations of artificial cells and organs, such as pancreas, urinary bladders, liver cells, and fibroblasts cells of foreskin and others. The principle of tissue engineering is described with various types of cells used for tissue engineering purposes. The use of several medical devices and bionics are mentioned with scaffold, cells and tissue cultures and various materials are used for biomedical engineering. The use of biomedical engineering methods is very important for the human health, and research and development of diseases. The bioreactors and preparations of artificial cells or tissues and organs are described here.
Caldeira, A Teresa; Arteiro, José M; Roseiro, José C; Neves, José; Vicente, H
2011-01-01
The combined effect of incubation time (IT) and aspartic acid concentration (AA) on the predicted biomass concentration (BC), Bacillus sporulation (BS) and anti-fungal activity of compounds (AFA) produced by Bacillus amyloliquefaciens CCMI 1051, was studied using Artificial Neural Networks (ANNs). The values predicted by ANN were in good agreement with experimental results, and were better than those obtained when using Response Surface Methodology. The database used to train and validate ANNs contains experimental data of B. amyloliquefaciens cultures (AFA, BS and BC) with different incubation times (1-9 days) using aspartic acid (3-42 mM) as nitrogen source. After the training and validation stages, the 2-7-6-3 neural network results showed that maximum AFA can be achieved with 19.5 mM AA on day 9; however, maximum AFA can also be obtained with an incubation time as short as 6 days with 36.6 mM AA. Furthermore, the model results showed two distinct behaviors for AFA, depending on IT. Copyright © 2010 Elsevier Ltd. All rights reserved.
Does Arctic governance hold the key to achieving climate policy targets?
NASA Astrophysics Data System (ADS)
Forbis, Robert, Jr.; Hayhoe, Katharine
2018-02-01
Arctic feedbacks are increasingly viewed as the wild card in the climate system; but their most unpredictable and potentially dangerous aspect may lie in the human, rather than the physical, response to a warming climate. If Arctic policy is driven by agendas based on domestic resource development, the ensuing oil and gas extraction will ensure the failure of the Paris Agreement. If Arctic energy policy can be framed by the Arctic Council, however, its environmental agenda and fragmented governance structure offers the scientific community a fighting chance to determine the region’s energy future. Connecting Arctic climate science to resource economics via its unique governance structure is one of the most powerful ways the scientific community can protect the Arctic region’s environmental, cultural, and scientific resources, and influence international energy and climate policy.
Zaman, Jonas; Wiech, Katja; Claes, Nathalie; Van Oudenhove, Lukas; Van Diest, Ilse; Vlaeyen, Johan W S
2018-04-03
The extent to which pain-related expectations, known to affect pain perception, also affect perception of non-painful sensations remains unclear, as well as the potential role of unpredictability in this context. In a proprioceptive fear conditioning paradigm, various arm extension movements were associated with predictable and unpredictable electrocutaneous pain or its absence. During a subsequent test phase non-painful electrocutaneous stimuli with a high or low intensity were presented during movement execution. We used hierarchical drift diffusion modeling to examine the influence of expecting pain on the perceptual decision-making process underlying intensity perception of non-painful sensations. In the first experiment (n=36), the pain stimulus was never presented during the test phase after conditioning. In the second experiment (n=39), partial reinforcement was adopted to prevent extinction of pain expectations. In both experiments, movements that were associated with (un)predictable pain led to higher pain-expectancy, self-reported fear, unpleasantness and arousal, as compared to movements that were never paired with pain (effect sizes ηp ranging from .119 - .557; all p-values < .05). Only in the second experiment - when the threat of the pain US remained present - we found that the expectation of pain affected decision-making. Compared to the no pain condition, an a priori decision-making bias towards the high intensity decision threshold was found with the strongest bias during unpredictable pain (effect sizes ηp ranging from .469 - .504; all p-values < .001). Thus, the expectation of pain not only affects inferential processes for subsequent painful but also for non-painful bodily stimuli, with unpredictability moderating these effects, and only when the threat of pain remains present due to partial reinforcement.
Chaby, Lauren E; Cavigelli, Sonia A; White, Amanda; Wang, Kayllie; Braithwaite, Victoria A
2013-01-01
Animals that experience adverse events in early life often have life-long changes to their physiology and behavior. Long-term effects of stress during early life have been studied extensively, but less attention has been given to the consequences of negative experiences solely during the adolescent phase. Adolescence is a particularly sensitive period of life when regulation of the glucocorticoid "stress" hormone response matures and specific regions in the brain undergo considerable change. Aversive experiences during this time might, therefore, be expected to generate long-term consequences for the adult phenotype. Here we investigated the long-term effects of exposure to chronic unpredictable stress during adolescence on adult decision-making, coping response, cognitive bias, and exploratory behavior in rats. Rats exposed to chronic unpredictable stress (e.g., isolation, crowding, cage tilt) were compared to control animals that were maintained in standard, predictable conditions throughout development. Unpredictable stress during adolescence resulted in a suite of long-term behavioral and cognitive changes including a negative cognitive bias [F (1, 12) = 5.000, P < 0.05], altered coping response [T (1, 14) = 2.216, P = 0.04], and accelerated decision-making [T (1, 14) = 3.245, P = 0.01]. Exposure to chronic stress during adolescence also caused a short-term increase in boldness behaviors; in a novel object test 15 days after the last stressor, animals exposed to chronic unpredictable stress had decreased latencies to leave a familiar shelter and approach a novel object [T (1, 14) = 2.240, P = 0.04; T (1, 14) = 2.419, P = 0.03, respectively]. The results showed that stress during adolescence has long-term impacts on behavior and cognition that affect the interpretation of ambiguous stimuli, behavioral response to adverse events, and how animals make decisions.
Figueredo, Aurelio José; Ellis, Bruce J.
2010-01-01
The National Longitudinal Study of Adolescent Health data were used to test predictions from life history theory. We hypothesized that (1) in young adulthood an emerging life history strategy would exist as a common factor underlying many life history traits (e.g., health, relationship stability, economic success), (2) both environmental harshness and unpredictability would account for unique variance in expression of adolescent and young adult life history strategies, and (3) adolescent life history traits would predict young adult life history strategy. These predictions were supported. The current findings suggest that the environmental parameters of harshness and unpredictability have concurrent effects on life history development in adolescence, as well as longitudinal effects into young adulthood. In addition, life history traits appear to be stable across developmental time from adolescence into young adulthood. PMID:20634914
Sadeghi, Arian; Ullenhag, Gustav; Wagenius, Gunnar; Tötterman, Thomas H; Eriksson, Fredrik
2013-06-01
Successful cell therapy relies on the identification and mass expansion of functional cells for infusion. Cryopreservation of cells is an inevitable step in most cell therapies which also entails consequences for the frozen cells. This study assessed the impact of cryopreservation and the widely used protocol for rapid expansion of T lymphocytes. The effects on cell viability, immunocompetence and the impact on apoptotic and immunosuppressive marker expression were analyzed using validated assays. Cryopreservation of lymphocytes during the rapid expansion protocol did not affect cell viability. Lymphocytes that underwent mass expansion or culture in high dose IL-2 were unable to respond to PHA stimulation by intracellular ATP production immediately after thawing (ATP = 16 ± 11 ng/ml). However, their reactivity to PHA was regained within 48 hours of recovery (ATP = 356 ± 61 ng/ml). Analysis of mRNA levels revealed downregulation of TGF-β and IL-10 at all time points. Culture in high dose IL-2 led to upregulation of p73 and BCL-2 mRNA levels while FoxP3 expression was elevated after culture in IL-2 and artificial TCR stimuli. FoxP3 levels decreased after short-term recovery without IL-2 or stimulation. Antigen specificity, as determined by IFNγ secretion, was unaffected by cryopreservation but was completely lost after addition of high dose IL-2 and artificial TCR stimuli. In conclusion, allowing short-time recovery of mass expanded and cryopreserved cells before reinfusion could enhance the outcome of adoptive cell therapy as the cells regain immune competence and specificity.
First step in developing a 3D biodegradable fibrin scaffold for an artificial ovary.
Luyckx, Valérie; Dolmans, Marie-Madeleine; Vanacker, Julie; Scalercio, Sarah R; Donnez, Jacques; Amorim, Christiani A
2013-11-25
Although transplantation of cryopreserved ovarian tissue is a promising approach to restore fertility in cancer patients, it is not advisable for women at risk of ovarian involvement due to the threat of reintroducing malignant cells. The aim of this study was therefore to find an alternative for these patients by development of an artificial ovary. For construction of the artificial ovary matrix, we used a central composite design to investigate nine combinations of fibrinogen (mg/ml) and thrombin (IU/mL) (F/T): F1/T4, F12.5/T1, F12.5/T20, F25/T0.1, F25/T4, F25/T500, F50/T1, F50/T20 and F100/T4. From the first qualitative analyses (handling and matrix size), five combinations (F12.5/T1, F25/T4, F50/T20, F50/T1 and F100/T4) yielded positive results. They were further evaluated in order to assess fibrin matrix degradation and homogeneous cell encapsulation (density), survival and proliferation (Ki67), and atresia (TUNEL) before and after 7 days of in vitro culture. To determine the best compromise between maximizing the dynamic density (Y1) and minimizing the apoptosis rate (Y2), we used the desirability function approach. Two combinations (F12.5/T1 and F25/T4) showed greater distribution of cells before in vitro culture, reproducible degradation of the fibrin network and adequate support for isolated human ovarian stromal cells, with a high proportion of Ki67-positive cells. SEM analysis revealed a network of fibers with regular pores and healthy stromal cells after in vitro culture with both F/T combinations. This study reports two optimal F/T combinations that allow survival and proliferation of isolated human ovarian cells. Further studies are required to determine if such a scaffold will also be a suitable environment for isolated ovarian follicles.
Egg-in-Cube: Design and Fabrication of a Novel Artificial Eggshell with Functionalized Surface
Huang, Wenjing; Arai, Fumihito; Kawahara, Tomohiro
2015-01-01
An eggshell is a porous microstructure that regulates the passage of gases to allow respiration. The chick embryo and its circulatory system enclosed by the eggshell has become an important model for biomedical research such as the control of angiogenesis, cancer therapy, and drug delivery test, because the use of embryo is ethically acceptable and it is inexpensive and small. However, chick embryo and extra-embryonic blood vessels cannot be accessed freely and has poor observability because the eggshell is tough and cannot be seen through, which limits its application. In this study, a novel artificial eggshell with functionalized surface is proposed, which allows the total amount of oxygen to pass into the egg for the chick embryo culturing and has high observability and accessibility for embryo manipulation. First, a 40-mm enclosed cubic-shaped eggshell consisting of a membrane structure and a rigid frame structure is designed, and then the threshold of the membrane thickness suitable for the embryo survival is figured out according to the oxygen-permeability of the membrane structure. The designed artificial eggshell was actually fabricated by using polydimethylsiloxane (PDMS) and polycarbonate (PC) in the current study. Using the fabricated eggshell, chick embryo and extra-embryonic blood vessels can be observed from multiple directions. To test the effectiveness of the design, the cubic eggshells were used to culture chick embryos and survivability was confirmed when PDMS membranes with adequate oxygen permeability were used. Since the surface of the eggshell is transparent, chick embryo tissue development could be observed during the culture period. Additionally, the chick embryo tissues could be accessed and manipulated from outside the cubic eggshell, by using mechanical tools without breakage of the eggshell. The proposed “Egg-in-Cube” with functionalized surface has great potential to serve as a promising platform for biomedical research. PMID:25768929
A Systemic Assessment Model for Al-Qaida’s Global Jihad
2013-04-11
war as a holy trinity consisting of enmity, chance, and reason; the interaction of which resembles the unpredictable motion of “an object suspended...between three magnets .”13 In other words, the participants in war interact with each other to produce nonlinear and unpredictable outcomes...may also drive requirements for new means. Systemic Assessment represents a perpetual feedback loop that repeatedly updates the commander’s
The CRH1 antagonist GSK561679 increases human fear but not anxiety as assessed by startle.
Grillon, Christian; Hale, Elizabeth; Lieberman, Lynne; Davis, Andrew; Pine, Daniel S; Ernst, Monique
2015-03-13
Fear to predictable threat and anxiety to unpredictable threat reflect distinct processes mediated by different brain structures, the central nucleus of the amygdala and the bed nucleus of the stria terminalis (BNST), respectively. This study tested the hypothesis that the corticotropin-releasing factor (CRF1) antagonist GSK561679 differentially reduces anxiety but increases fear in humans. A total of 31 healthy females received each of four treatments: placebo, 50 mg GSK561679 (low-GSK), 400 mg GSK561679 (high-GSK), and 1 mg alprazolam in a crossover design. Participants were exposed to three conditions during each of the four treatments. The three conditions included one in which predictable aversive shocks were signaled by a cue, a second during which shocks were administered unpredictably, and a third condition without shock. Fear and anxiety were assessed using the acoustic startle reflex. High-GSK had no effect on startle potentiation during unpredictable threat (anxiety) but increased startle potentiation during the predictable condition (fear). Low-GSK did not affect startle potentiation across conditions. Consistent with previous findings, alprazolam reduced startle potentiation during unpredictable threat but not during predictable threat. The increased fear by high-GSK replicates animal findings and suggests a lift of the inhibitory effect of the BNST on the amygdala by the CRF1 antagonist.
NASA Astrophysics Data System (ADS)
Suantika, Gede; Anggraeni, Jayanty; Hasby, Fahri Azhari; Yanuwiarti, Ni Putu Indah
2014-03-01
Litopenaeus vannamei or white leg shrimp is an introduced shrimp which has successfully cultured in Indonesia. In Indonesia, L. vannamei is commonly cultured on outdoor/earthen pond that requires renewal of water, less control in term of water quality and disease and attributed to unpredictable yield production. Based on the existing culture condition, a system that enable to minimize water consumption, improve the hygiene of the culture and at the same time maintain a more stable yield production is urgent to be developed by using a zero water discharge system. The system consists of: (a) culture tank - to retain and culture the shrimp; (b) CaCO3 grained - buffering agent and substrate of nitrifying bacteria; (c) aeration line - to provide O2 and homogenize the culture; (d) ancho (feeding) - to control an appropriate feed; (e) nitrifying bacteria adding - to consume ammonium and nitrite then convert it to nitrate, and also control pathogen Vibrio sp.; (f) diatom microalgae (Chaetoceros gracilis) - to uptake nitrate, bacteriostatic agent, feed source, provide O2 and shading. In this study, there were 2 treatments: the static culture (batch) system was set as control (K) (in 70 PL/m2), and culture system with zero-water discharge system which was inoculated by 0.02% v/v 106 CFU/ml of mixed culture nitrifying bacteria and diatom microalgae in 70 PL/m2 (P1). The white leg shrimp used in this experiment was at post larvae (PL) 10 and cultured in a batch system (1 × 1 × 0.5 m3 pond) during 2 months. Several parameters including survival rate, mean body weight, and water quality (salinity, temperature, pH, DO, ammonium, nitrite, and nitrate) were measured. Based on the results, biomass of P1 (237.12 ± 31.11) gram is significantly higher than control (K) (180.80 ± 12.26) gram (P< 0,05). Water quality during the culture period in all treatments were still in tolerance range of white leg shrimp post larvae, except ammonium concentration in control (K) (2.612 ± 0.56) mg/L which is significantly different from P1 (1.287 ± 0.49) mg/L. Based on this research, zero-water discharge technology using nitrifying bacteria and diatom microalgae can improve productivity of white shrimp by increasing the biomass and maintaining a stable water quality especially ammonium concentration.
Artsatbanov, V Yu; Vostroknutova, G N; Shleeva, M O; Goncharenko, A V; Zinin, A I; Ostrovsky, D N; Kapreliants, A S
2012-04-01
Artificial generation of oxygen superoxide radicals in actively growing cultures of Mycobacterium tuberculosis, Myc. smegmatis, and Corynebacterium ammoniagenes is followed by accumulation in the bacterial cells of substantial amounts of 2-C-methyl-D-erythritol-2,4-cyclodiphosphate (MEcDP) - an intermediate of the non-mevalonate pathway of isoprenoid biosynthesis (MEP) - most possibly due to the interaction of the oxygen radicals with the 4Fe-4S group in the active center and inhibition of the enzyme (E)-4-oxy-3-methylbut-2-enyl diphosphate synthase (IspG). Cadmium ions known to inhibit IspG enzyme in chloroplasts (Rivasseau, C., Seemann, M., Boisson, A. M., Streb, P., Gout, E., Douce, R., Rohmer, M., and Bligny, R. (2009) Plant Cell Environ., 32, 82-92), when added to culture of Myc. smegmatis, substantially increase accumulation of MEcDP induced by oxidative stress with no accumulation of other organic phosphate intermediates in the cell. Corynebacterium ammoniagenes'', well-known for its ability to synthesize large amounts of MEcDP, was also shown to accumulate this unique cyclodiphosphate in actively growing culture when NO at low concentration is artificially generated in the medium. A possible role of the MEP-pathway of isoprenoid biosynthesis and a role of its central intermediate MEcDP in bacterial response to nitrosative and oxidative stress is discussed.
van der Steen, Jenny T; Hertogh, Cees M P M; de Graas, Tjomme; Nakanishi, Miharu; Toscani, Franco; Arcand, Marcel
2013-02-01
Families of patients with dementia may need support in difficult end-of-life decision making. Such guidance may be culturally sensitive. To support families in Canada, a booklet was developed to aid decision making on palliative care issues. For reasons of cost effectiveness and promising effects, we prepared for its implementation in Italy, the Netherlands and Japan. Local teams translated and adapted the booklet to local ethical, legal and medical standards where needed, retaining guidance on palliative care. Using qualitative content analyses, we grouped and compared adaptations to understand culturally sensitive aspects. Three themes emerged: (1) relationships among patient, physician and other professionals-the authority of the physician was more explicit in adapted versions; (2) patient rights and family position-adding detail about local regulations; and (3) typology of treatments and decisions. Considerations underlying palliative care decisions were detailed (Dutch and Italian versions), and the Japanese version frequently referred to professional and legal standards, and life-prolongation was a competing goal. Text on artificial feeding or fluids and euthanasia was revised extensively. Providing artificial feeding and fluids and discussing euthanasia may be particularly sensitive topics, and guidance on these subjects needs careful consideration of ethical aspects and possible adaptations to local standards and practice. The findings may promote cross-national debate on sensitive, core issues regarding end-of-life care in dementia.
Glady-Croue, Julie; Niu, Xi-Zhi; Ramsay, Joshua P; Watkin, Elizabeth; Murphy, Riley J T; Croue, Jean-Philippe
2018-06-01
Urban wastewater treatment plant effluents represent one of the major emission sources of antibiotic-resistant bacteria (ARB) in natural aquatic environments. In this study, the effect of artificial solar radiation on total culturable heterotrophic bacteria and ARB (including amoxicillin-resistant, ciprofloxacin-resistant, rifampicin-resistant, sulfamethoxazole-resistant, and tetracycline-resistant bacteria) present in secondary effluent was investigated. Artificial solar radiation was effective in inactivating the majority of environmental bacteria, however, the proportion of strains with ciprofloxacin-resistance and rifampicin-resistance increased in the surviving populations. Isolates of Pseudomonas putida, Serratia marcescens, and Stenotrophomonas maltophilia nosocomial pathogens were identified as resistant to solar radiation and to at least three antibiotics. Draft genome sequencing and typing revealed isolates carrying multiple resistance genes; where S. maltophilia (resistant to all studied antibiotics) sequence type was similar to strains isolated in blood infections. Results from this study confirm that solar radiation reduces total bacterial load in secondary effluent, but may indirectly increase the relative abundance of ARB. Copyright © 2018 Elsevier B.V. All rights reserved.
Carbon dioxide dynamics in an artificial ecosystem
NASA Astrophysics Data System (ADS)
Hu, Enzhu; Hu, Dawei; Tong, Ling; Li, Ming; Fu, Yuming; He, Wenting; Liu, Hong
An experimental artificial ecosystem was established as a tool to understand the behavior of closed ecosystem and to develop the technology for a future bioregenerative life support system for lunar or planetary exploration. Total effective volume of the system is 0.7 m3 . It consists of a higher plant chamber, an animal chamber and a photo-bioreactor which cultivated lettuce (Lactuca sativa L.), silkworm (Bombyx Mori L.) and microalgae (Chlorella), respectively. For uniform and sustained observations, lettuce and silkworms was cultivated using sequential cultivation method, and microalgae using continuous culture. Four researchers took turns breathing the system air through a tube for brief periods every few hours. A mathematic model, simulating the carbon dioxide dynamics was developed. The main biological parameters concerning photosynthesis of lettuce and microalgae, respiration of silkworms and human were validated by the experimental data. The model described the respiratory relationship between autotrophic and heterotrophic compartments. A control strategy was proposed as a tool for the atmosphere management of the artificial ecosystem.
Functional artificial luciferases as an optical readout for bioassays.
Kim, Sung Bae; Izumi, Hiroshi
2014-06-13
This study elucidates functional artificial luciferases (ALucs) wholly synthesized for bioassays and molecular imaging. The ALucs bearing epitopes were newly created by amending the sequences of our previously reported ALucs in light of a multi-sequence alignment and hydrophobicity search. The synthesized ALucs are survived in live cells and stable in culture media for 25 days after secretion. The epitopes in ALucs are exposed during the secretion process and indeed valid for column purification and immunological assays. The ALucs exerted a 9400-times stronger optical intensity with a coelenterazine derivative (CTZ i), when compared with Renilla reniformis luciferase 8.6-535. A supersecondary structure of ALuc30 was predicted with respect to the X-ray crystallographic information of the coelenterazine-binding protein (CBP). The structure revealed that ALuc30 has a room for accommodating the iodide of CTZ i. This study guides on how to create functional artificial luciferases and predicts the structural details with the current bioinformatics technologies. Copyright © 2014 Elsevier Inc. All rights reserved.
Feng, Yong-wen; Wu, Ming; Li, Ying; Zeng, Jing-jing; Li, Ming-li; He, Yun; Li, Dan-hui; Cui, Man-li
2012-02-01
To investigate the direct relationship and significance between the pH value of gastric juice and positive fungi in culture critical patients with artificial airway in intensive care unit (ICU) by analyzing and identifying the type of fungi and their sensitivity to antifungal therapy. A prospective study was conducted.One hundred and sixty patients (between December, 2008 and October, 2011) with artificial airway lasting longer than 48 hours were studied in the ICU at the First Affiliated Hospital of Shenzhen University. The gastric juice specimens were collected through a nasogastric tube, their pH values were measured using precise litmus paper. These samples were divided into six groups according to their pH values: pH ≤ 2.0, pH 2.1-3.0, pH 3.1-4.0, pH 4.1-5.0, pH 5.1-6.0 and pH 6.1-7.0, and then fungi were cultured in these specimens with different pH values. Susceptibility of different fungicide drugs were also investigated. The susceptibility of fungi to gastric juice with different pH values was also investigated. The relationship between 28-day survival rate and the presence of fungi in gastric juice was analyzed in order to analyze the relationship of the presence of fungi in gastric juice and clinical outcome. (1) No fungal growth was found in the gastric juice with pH value lower than 4.0, and the positive rate of fungal culture was significantly increased when the pH value of gastric juice raised. (2) The positive rate of fungal growth was 27.9% (55/197), in which, the positive rate of Candida and non-Candida fungi was 38.2% (21/55) and 61.8% (34/55) respectively, and the difference was significant statistically [χ(2) = 4.16, P < 0.05]. (3) The fungal positive rate was 40.0% (22/55) and 60.0% (33/55) respectively, in survivors (102 cases) and non-survivors (58 cases). The percentage of Candida infection and non-Candida infection was 54.5% (12/22) and 45.5% (10/22) respectively, in survivors, and it was 27.3% (9/33) and 72.7% (24/33), respectively, in non-survivors. The rate of resistance of Candida and non-Candida fungi was 4.7%-14.3% (mean 10.1%) and 0-60% (mean 28.5%) respectively. Positive fungus culture rate was higher in critical patients with artificial airway and higher gastric juice pH values. Non-Candida fungi were mainly found in gastric juice with increasing resistance rate. Candida was more commonly found in survivors, and non-Candida fungi were more commonly found in non-survivors.
Detraditionalisation and attitudes to sex outside marriage in China.
Zheng, Weijun; Zhou, Xudong; Zhou, Chi; Liu, Wei; Li, Lu; Hesketh, Therese
2011-05-01
China has undergone massive socio-economic change over the past 30 years. In parallel, there have been huge changes in social and sexual mores. Until the end of the Mao era strict norms prevailed, with sex outside marriage widely regarded as immoral and unacceptable. Detraditionalisation theory describes the abandonment or reconfiguration of the socio-cultural traditions and has been explored widely in Western settings. This study aimed to explore its relevance for China through exploring attitudes towards premarital sex, extramarital sex, same-sex relations and sex work. We conducted semi-structured interviews with 212 men and women aged 18 to 39 in urban and rural areas of three provinces: Zhejiang, Guizhou and Yunnan. Analysis identified emerging themes. Results show varying degrees of acceptance of the four sexual behaviours, with premarital sex seen as common, homosexuality still regarded as unacceptable by the majority but considerable acceptance of commercial sex work as part of male business transactions and social life. China appears to be on a pathway of detraditionalisation with specific Chinese features. This study suggests that the concept of detraditionalisation applies well to non-Western contexts, but the path it takes is culture-specific and relatively unpredictable. © 2011 Taylor & Francis
Stability of Trifluoromethane in Forest Soils and Methanotrophic Cultures
NASA Technical Reports Server (NTRS)
King, Gary M.
1997-01-01
Trifluoromethane (TFM) has been reported as an endproduct of trifluoroacetate degradation under oxic conditions. Although other halomethanes, such as chloroform, methyl bromide, and methyl fluoride, inhibit methane oxidation or are degraded by methanotrophs, the fate of TFM is unknown. TFM had no affect on atmospheric methane consumption when added to forest soils at either 10 ppm or 10,000 ppm. No degradation of TFM was observed at either concentration for incubations of 6 days. Cultures of Methylobacter albus BG8 and Methylosinus trichosporium OB3b grown With and without added copper were also used to assay TFM degradation at 10 10000 ppm levels. TFM did not inhibit methane oxidation under any growth conditions, including those inducing expression of soluble methane monooxygenase, nor was it degraded at measurable rates. In contrast, parallel assays showed that both methyl fluoride and chloroform inhibited methane oxidation in M. trichosporium OB3b. Our results suggest that TFM may be relatively inert with respect to methanotrophic degradition. Although TFM has a negligible ozone depletion potential, it absorbs infrared radiation and has a relatively long atmospheric residence time. Thus, accumulation of TFM in the atmosphere as a consequence of the decomposition of hydrochlorofluorocarbons may have significant unpredicted climate impacts.
Chang, Chung-Liang; Huang, Yi-Ming; Hong, Guo-Fong
2015-01-01
The direction of sunshine or the installation sites of environmental control facilities in the greenhouse result in different temperature and humidity levels in the various zones of the greenhouse, and thus, the production quality of crop is inconsistent. This study proposed a wireless-networked decentralized fuzzy control scheme to regulate the environmental parameters of various culture zones within a greenhouse. The proposed scheme can create different environmental conditions for cultivating different crops in various zones and achieve diversification or standardization of crop production. A star-type wireless sensor network is utilized to communicate with each sensing node, actuator node, and control node in various zones within the greenhouse. The fuzzy rule-based inference system is used to regulate the environmental parameters for temperature and humidity based on real-time data of plant growth response provided by a growth stage selector. The growth stage selector defines the control ranges of temperature and humidity of the various culture zones according to the leaf area of the plant, the number of leaves, and the cumulative amount of light. The experimental results show that the proposed scheme is stable and robust and provides basis for future greenhouse applications. PMID:26569264
Growing Bladder-Cancer Cells In Three-Dimensional Clusters
NASA Technical Reports Server (NTRS)
Spaulding, Glenn F.; Prewett, Tacey L.; Goodwin, Thomas J.
1995-01-01
Artificial growth process helps fill gaps in cancer research. Cell cultures more accurate as models for in vivo studies and as sources of seed cells for in vivo studies. Effected in horizontal rotating bioreactor described in companion article, "Simplified Bioreactor for Growing Mammalian Cells" (MSC-22060). Provides aggregates of cells needed to fill many of gaps.
Relationships among attention networks and physiological responding to threat.
Sarapas, Casey; Weinberg, Anna; Langenecker, Scott A; Shankman, Stewart A
2017-02-01
Although researchers have long hypothesized a relationship between attention and anxiety, theoretical and empirical accounts of this relationship have conflicted. We attempted to resolve these conflicts by examining relationships of attentional abilities with responding to predictable and unpredictable threat - related but distinct motivational process implicated in a number of anxiety disorders. Eighty-one individuals completed a behavioral task assessing efficiency of three components of attention - alerting, orienting, and executive control (Attention Network Test - Revised). We also assessed startle responding during anticipation of both predictable, imminent threat (of mild electric shock) and unpredictable contextual threat. Faster alerting and slower disengaging from non-emotional attention cues were related to heightened responding to unpredictable threat, whereas poorer executive control of attention was related to heightened responding to predictable threat. This double dissociation helps to integrate models of attention and anxiety and may be informative for treatment development. Copyright © 2016 Elsevier Inc. All rights reserved.
[Unpredictable chronic mild stress effects on antidepressants activities in forced swim test].
Kudryashov, N V; Kalinina, T S; Voronina, T A
2015-02-01
The experiments has been designed to study unpredictable chronic mild stress effect on anti-depressive activities of amitriptyline (10 mg/kg) and fluoxetine (20 mg/kg) in forced swim test in male outbred mice. It is shown that acute treatment with fluoxetine does not produce any antidepressant effects in mice following stress of 14 days while the sub-chronic injections of fluoxetine result in more deep depressive-like behavior. In 28 daily stressed mice, antidepressant effect of fluoxetine is observed independently of the injection rates. Amitriptyline demonstrates the antidepressant activity regardless of the duration of stress or administration scheduling, but at the same time the severity of anti-immobilization effect of amitriptyline in stressed mice is weaker in compare to non-stressed trails. Thus, the injection rates and duration of unpredictable mild chronic stress are the parameters that determine the efficiency of antidepressants in the mouse forced swimming test.
Nimmo, Lisa M; Lewandowsky, Stephan
2006-09-01
The notion of a link between time and memory is intuitively appealing and forms the core assumption of temporal distinctiveness models. Distinctiveness models predict that items that are temporally isolated from their neighbors at presentation should be recalled better than items that are temporally crowded. By contrast, event-based theories consider time to be incidental to the processes that govern memory, and such theories would not imply a temporal isolation advantage unless participants engaged in a consolidation process (e.g., rehearsal or selective encoding) that exploited the temporal structure of the list. In this report, we examine two studies that assessed the effect of temporal distinctiveness on memory, using auditory (Experiment 1) and auditory and visual (Experiment 2) presentation with unpredictably varying interitem intervals. The results show that with unpredictable intervals temporal isolation does not benefit memory, regardless of presentation modality.
Relationships Among Attention Networks and Physiological Responding to Threat
Sarapas, Casey; Weinberg, Anna; Langenecker, Scott A.
2016-01-01
Although researchers have long hypothesized a relationship between attention and anxiety, theoretical and empirical accounts of this relationship have conflicted. We attempted to resolve these conflicts by examining relationships of attentional abilities with responding to predictable and unpredictable threat, related but distinct motivational process implicated in a number of anxiety disorders. Eighty-one individuals completed a behavioral task assessing efficiency of three components of attention – alerting, orienting, and executive control (Attention Network Test - Revised). We also assessed startle responding during anticipation of both predictable, imminent threat (of mild electric shock) and unpredictable contextual threat. Faster alerting and slower disengaging from non-emotional attention cues were related to heightened responding to unpredictable threat, whereas poorer executive control of attention was related to heightened responding to predictable threat. This double dissociation helps to integrate models of attention and anxiety and may be informative for treatment development. PMID:27816781
Asnani, Monika Rani; Barton-Gooden, Antoinette; Grindley, Marlyn; Knight-Madden, Jennifer
2017-01-01
Disease knowledge, illness perceptions, and quality of life (QOL) were examined in 150 adolescents (mean age = 16.1 years, SD = 1.9; 49.3% males) with sickle cell disease (SCD). Females had higher knowledge (P = .004), lower QOL (P = .02), and perceived their illness to be more unpredictable (P = .03). Those with more severe disease perceived their illness to be unpredictable with worse outcomes. Those with higher knowledge scores perceived their illness to be chronic, made more sense of their illness, and perceived greater personal and treatment control. Final hierarchical regression model showed that secondary education as compared to primary education level (P < .001) was positively correlated whereas disease severity (P < .001), perceived unpredictability (P = .024), and negative emotions (P < .001) were negatively correlated with QOL. Health practitioners should assess adolescents’ illness perceptions and encouraging continuing schooling and addressing emotional/psychological problems could improve their QOL. PMID:29152543
NASA Astrophysics Data System (ADS)
Curiac, Daniel-Ioan; Volosencu, Constantin
2014-10-01
The path-planning algorithm represents a crucial issue for every autonomous mobile robot. In normal circumstances a patrol robot will compute an optimal path to ensure its task accomplishment, but in adversarial conditions the problem is getting more complicated. Here, the robot’s trajectory needs to be altered into a misleading and unpredictable path to cope with potential opponents. Chaotic systems provide the needed framework for obtaining unpredictable motion in all of the three basic robot surveillance missions: area, points of interests and boundary monitoring. Proficient approaches have been provided for the first two surveillance tasks, but for boundary patrol missions no method has been reported yet. This paper addresses the mentioned research gap by proposing an efficient method, based on chaotic dynamic of the Hénon system, to ensure unpredictable boundary patrol on any shape of chosen closed contour.
Uncertainty in macroeconomic policy-making: art or science?
Aikman, David; Barrett, Philip; Kapadia, Sujit; King, Mervyn; Proudman, James; Taylor, Tim; de Weymarn, Iain; Yates, Tony
2011-12-13
Uncertainty is pervasive in economic policy-making. Modern economies share similarities with other complex systems in their unpredictability. But economic systems also differ from those in the natural sciences because outcomes are affected by the state of beliefs of the systems' participants. The dynamics of beliefs and how they interact with economic outcomes can be rich and unpredictable. This paper relates these ideas to the recent crisis, which has reminded us that we need a financial system that is resilient in the face of the unpredictable and extreme. It also highlights how such uncertainty puts a premium on sound communication strategies by policy-makers. This creates challenges in informing others about the uncertainties in the economy, and how policy is set in the face of those uncertainties. We show how the Bank of England tries to deal with some of these challenges in its communications about monetary policy.
Occurrence of Anthracnose on Fruits of Asian Pear Tree Caused by Colletotrichum acutatum.
Kim, Wan Gyu; Hong, Sung Kee; Park, Yeong Seob
2007-12-01
Anthracnose symptoms often occurred on fruits of Asian pear trees grown in Anseong, Naju, Seonghwan and Pyeongtaek in Korea during the harvesting period from 2000 to 2005. A total of 28 isolates of Colletotrichum sp. were obtained from the anthracnose symptoms. All the isolates were identified as Colletotrichum acutatum based on their morphological and cultural characteristics. Four isolates of the fungus were tested for pathogenicity to fruits of Asian pear tree by artificial inoculation. All the isolates induced anthracnose symptoms on the fruits by wound inoculation but not by unwound inoculation. The anthracnose symptoms induced by artificial inoculation were similar to those observed in the orchard. This is the first report of anthracnose of Asian pear tree caused by Colletotrichum acutatum.
Li, L; Lu, G
2005-01-01
This paper investigates the efficiency of application of medical ethics principles in the practice of artificial insemination by donors (AID) in China, in a culture characterised by traditional ethical values and disapproval of AID. The paper presents the ethical approach to AID treatment as established by the Reproduction and Genetics Hospital of CITIC-Xiangya (CITIC Hunan-Yale Approach) in the central southern area of China against the social ethical background of China and describes its general features. The CITIC-Xiangya Approach facilitates the implementation of ethical relations between clinicians and patients participating in AID treatment procedures in Hunan-Yale. PMID:15923480
Gender Differences in Sexual Attraction and Moral Judgment: Research With Artificial Face Models.
González-Álvarez, Julio; Cervera-Crespo, Teresa
2018-01-01
Sexual attraction in humans is influenced by cultural or moral factors, and some gender differences can emerge in this complex interaction. A previous study found that men dissociate sexual attraction from moral judgment more than women do. Two experiments consisting of giving attractiveness ratings to photos of real opposite-sex individuals showed that men, compared to women, were significantly less influenced by the moral valence of a description about the person shown in each photo. There is evidence of some processing differences between real and artificial computer-generated faces. The present study tests the robustness of González-Álvarez's findings and extends the research to an experimental design using artificial face models as stimuli. A sample of 88 young adults (61 females and 27 males, average age 19.32, SD = 2.38) rated the attractiveness of 80 3D artificial face models generated with the FaceGen Modeller 3.5 software. Each face model was paired with a "good" and a "bad" (from a moral point of view) sentence depicting a quality or activity of the person represented in the model (e.g., she/he is an altruistic nurse in Africa vs. she/he is a prominent drug dealer). Results were in line with the previous findings and showed that, with artificial faces as well, sexual attraction is less influenced by morality in men than in women. This gender difference is consistent with an evolutionary perspective on human sexuality.
NASA Astrophysics Data System (ADS)
Amranul Haque, Md; Nagaoka, Masato; Hexig, Bayar; Akaike, Toshihiro
2010-02-01
Nanobiomaterials can play a central role in regenerative medicine and tissue engineering by facilitating cellular behavior and function, such as those where extracellular matrices (ECMs) direct embryonic stem (ES) cell morphogenesis, proliferation, differentiation and apoptosis. However, controlling ES cell proliferation and differentiation using matrices from natural sources is still challenging due to complex and heterogeneous culture conditions. Moreover, the systemic investigation of the regulation of self-renewal and differentiation to lineage specific cells depends on the use of defined and stress-free culture conditions. Both goals can be achieved by the development of biomaterial design targeting ECM or growth factors for ES cell culture. This targeted application will benefit from expansion of ES cells for transplantation, as well as the production of a specific differentiated cell type either by controlling the differentiation in a very specific pathway or by elimination of undesirable cell types.
Akay, Canan; Tanış, Merve Ç; Sevim, Handan
2017-10-13
The aim of this study was to evaluate the cytotoxic effects of 9 different soft denture liners on the viability of L-929 mouse fibroblast cells at different incubation periods by storing them in artificial saliva (AS) with different pH levels. 96 disk samples from each lining material were prepared and divided into 4 groups: GI: No treatment; GII: Stored in artificial saliva with pH 3 for 21 days; Group III: Stored in artificial saliva with pH 7 for 21 days; and Group IV: Stored in artificial saliva with pH 14 for 21 days. The cytotoxicity of the extracts to cultured mouse fibroblasts (L-929) was measured by MTT (tetrazolium salt 3-[4,5-dimethylthiazol-2-yl]-2,5-dipHnyltetrazolium bromide) assay. Data were analyzed using 1-way analysis of variation (ANOVA). It was found that for the pH 3 values of New Truliner, Trusoft, Mollosil Plus, Dentusil, TDV, and HydroCast®; for the pH 7 values of Ufi Gel P and Elite plus; and for the pH 14 values of HydroCast®, there was a noncytotoxic effect during both the 24-hour and 48-hour incubation periods. In the control group 48-hour incubation period, HydroCast®, TDV, Mollosil, 24-hour incubation period Elite plus, for pH 3 values; Elite Plus 24-hour incubation period, for pH 7 values Trusoft 48-hour incubation period there was a moderately cytotoxic effect. This in vitro study revealed that storage in artificial saliva with different pH levels can affect the cytotoxicity of soft lining materials.
NASA Astrophysics Data System (ADS)
Yucel, M.; Sueishi, T.; Inagaki, A.; Kanda, M.
2017-12-01
`Great Garuda' project is an eagle-shaped offshore structure with 17 artificial islands. This project has been designed for the coastal protection and land reclamation of Jakarta due to catastrophic flooding in the city. It offers an urban generation for 300.000 inhabitants and 600.000 workers in addition to its water safety goal. A broad coalition of Indonesian scientists has criticized the project for being negative impacts on the surrounding environment. Despite the vast research by Indonesian scientist on maritime environment, studies on wind and thermal environment over built-up area are still lacking. However, the construction of the various islands off the coast may result changes in wind patterns and thermal environment due to the alteration of the coastline and urbanization in the Jakarta Bay. Therefore, it is important to understand the airflow within the urban canopy in case of unpredictable gust events. These gust events may occur through the closely-packed high-rise buildings and pedestrians may be harmed from such gusts. Accordingly, we used numerical simulations to investigate the impact of the sea wall and the artificial islands over built-up area and, the intensity of wind gusts at the pedestrian level. Considering the fact that the size of turbulence organized structure sufficiently large computational domain is required. Therefore, a 19.2km×4.8km×1.0 km simulation domain with 2-m resolution in all directions was created to explicitly resolve the detailed shapes of buildings and the flow at the pedestrian level. This complex computation was accomplished by implementing a large-eddy simulation (LES) model. Two case studies were conducted considering the effect of realistic surface roughness and upward heat flux. Case_1 was conducted based on the current built environment and Case_2 for investigating the effect of the project on the chosen coastal region of the city. Fig.1 illustrates the schematic of the large-eddy simulation domains of two cases with and without Great Garuda Sea Wall and 17 artificial islands. 3D model of Great Garuda is shown in Fig.2. In addition to the cases mentioned above, the simulation will be generated assigning more realistic heat flux outputs from energy balance model and, inflow boundary conditions coupling with mesoscale model (Weather Research and Forecast model).
Kowinsky, Amy M; Shovel, Judith; McLaughlin, Maribeth; Vertacnik, Lisa; Greenhouse, Pamela K; Martin, Susan Christie; Minnier, Tamra E
2012-01-01
Predictable and unpredictable patient care tasks compete for caregiver time and attention, making it difficult for patient care staff to reliably and consistently meet patient needs. We have piloted a redesigned care model that separates the work of patient care technicians based on task predictability and creates role specificity. This care model shows promise in improving the ability of staff to reliably complete tasks in a more consistent and timely manner.
Distinct state anxiety after predictable and unpredictable fear training in mice.
Seidenbecher, Thomas; Remmes, Jasmin; Daldrup, Thiemo; Lesting, Jörg; Pape, Hans-Christian
2016-05-01
Sustained fear paradigms in rodents have been developed to monitor states of anxious apprehension and to model situations in patients suffering from long-lasting anxiety disorders. A recent report describes a fear conditioning paradigm, allowing distinction between phasic and sustained states of conditioned fear in non-restrained mice. However, so far no prospective studies have yet been conducted to elucidate whether induction of phasic or sustained fear can affect states of anxiety. Here, we used CS (conditioned stimulus) and US (unconditioned stimulus) pairing with predictable and unpredictable timing to induce phasic and sustained fear in mice. State anxiety during various fear response components was assessed using the elevated plus-maze test. Training with unpredictable CS-US timing resulted in CS-evoked sustained components of fear (freezing), while predictable CS-US timing resulted in rapid decline. Data suggested the influence of training procedure on state anxiety which is dependent on progression of conditioned fear during fear memory retrieval. Animals trained with unpredictable CS-US timing showed an unchanged high anxiety state throughout behavioral observation. In contrast, mice trained with predictable CS-US timing showed anxiolytic-like behavior 3 min after CS onset, which was accompanied by a fast decline of the fear conditioned response (freezing). Further systematic studies are needed to validate the phasic/sustained fear model in rodents as translational model for anxiety disorders in humans. Copyright © 2016 Elsevier B.V. All rights reserved.
The CRH1 Antagonist GSK561679 Increases Human Fear But Not Anxiety as Assessed by Startle
Grillon, Christian; Hale, Elizabeth; Lieberman, Lynne; Davis, Andrew; Pine, Daniel S; Ernst, Monique
2015-01-01
Fear to predictable threat and anxiety to unpredictable threat reflect distinct processes mediated by different brain structures, the central nucleus of the amygdala and the bed nucleus of the stria terminalis (BNST), respectively. This study tested the hypothesis that the corticotropin-releasing factor (CRF1) antagonist GSK561679 differentially reduces anxiety but increases fear in humans. A total of 31 healthy females received each of four treatments: placebo, 50 mg GSK561679 (low-GSK), 400 mg GSK561679 (high-GSK), and 1 mg alprazolam in a crossover design. Participants were exposed to three conditions during each of the four treatments. The three conditions included one in which predictable aversive shocks were signaled by a cue, a second during which shocks were administered unpredictably, and a third condition without shock. Fear and anxiety were assessed using the acoustic startle reflex. High-GSK had no effect on startle potentiation during unpredictable threat (anxiety) but increased startle potentiation during the predictable condition (fear). Low-GSK did not affect startle potentiation across conditions. Consistent with previous findings, alprazolam reduced startle potentiation during unpredictable threat but not during predictable threat. The increased fear by high-GSK replicates animal findings and suggests a lift of the inhibitory effect of the BNST on the amygdala by the CRF1 antagonist. PMID:25430779
Implications of life-history strategies for obesity
Maner, Jon K.; Dittmann, Andrea; Meltzer, Andrea L.; McNulty, James K.
2017-01-01
The association between low socioeconomic status (SES) and obesity is well documented. In the current research, a life history theory (LHT) framework provided an explanation for this association. Derived from evolutionary behavioral science, LHT emphasizes how variability in exposure to unpredictability during childhood gives rise to individual differences in a range of social psychological processes across the life course. Consistent with previous LHT research, the current findings suggest that exposure to unpredictability during childhood (a characteristic common to low SES environments) is associated with the adoption of a fast life-history strategy, one marked by impulsivity and a focus on short-term goals. We demonstrate that a fast life-history strategy, in turn, was associated with dysregulated weight-management behaviors (i.e., eating even in the absence of hunger), which were predictive of having a high body mass index (BMI) and being obese. In both studies, findings held while controlling for participants’ current socioeconomic status, suggesting that obesity is rooted in childhood experiences. A serial mediation model in study 2 confirmed that effects of childhood SES on adult BMI and obesity can be explained in part by exposure to unpredictability, the adoption of a fast life-history strategy, and dysregulated-eating behaviors. These findings suggest that weight problems in adulthood may be rooted partially in early childhood exposure to unpredictable events and environments. LHT provides a valuable explanatory framework for understanding the root causes of obesity. PMID:28739939
Shen, Jun; Xu, Linling; Qu, Chujie; Sun, Huimin; Zhang, Junjian
2018-04-30
Chronic unpredictable mild stress (CUMS) leads to neuropsychiatric disorders, such as depression, anxiety and cognitive impairment. Resveratrol is a natural polyphenol existed in polygonum cuspidatum and has been demonstrated to be a potent activator of Sirtuin 1 (Sirt1). Previous studies reported that resveratrol treatment ameliorated CUMS-induced depressive-like behavior and cognitive deficits through upregulating cAMP response element-binding protein (CREB) and brain derived neurotrophic factor (BDNF) expression. However, the upstream signalling pathway mediating CREB/BDNF expression and then exerting a protective role on cognitive function remains unclear. The present study aims to investigate the possible mechanism of resveratrol on CUMS-induced cognitive deficits. Male Sprague Dawley rats were adminstrated resveratrol (40 and 80 mg/kg) every day for 4 consecutive weeks before exposure to CUMS procedure. Morris Water Maze test was used to appraise spatial learing and memory of rats. Sirt1/miR-134 signalling pathway and CREB/BDNF expression in hippocampus of rats were measured. We also explored Sirt1/miR-134 signalling pathway and CREB/BDNF expression in primary cultured hippocampus neurons with resveratrol (25, 50 and 100 μmol/L) treatment. We found that resveratrol treatment prevented spatial learing and memory impairment induced by CUMS. Meanwhile the potential mechanism of resveratrol was associated with increased levels of Sirt1, CREB phosphorylation (p-CREB), CREB, BDNF and decreased levels of miR-134 in vivo and in vitro. In conclusion, our study showed that the neuroprotective effect of resveratrol on CUMS-induced cognitive impairment may rely on activating Sirt1/miR-134 pathway and then upregulating its downstream CREB/BDNF expression in hippocampus. Copyright © 2018 Elsevier B.V. All rights reserved.
Banasr, Mounira; Lepack, Ashley; Fee, Corey; Duric, Vanja; Maldonado-Aviles, Jaime; DiLeone, Ralph; Sibille, Etienne; Duman, Ronald S.; Sanacora, Gerard
2017-01-01
Evidence continues to build suggesting that the GABAergic neurotransmitter system is altered in brains of patients with major depressive disorder. However, there is little information available related to the extent of these changes or the potential mechanisms associated with these alterations. As stress is a well-established precipitant to depressive episodes, we sought to explore the impact of chronic stress on GABAergic interneurons. Using western blot analyses and quantitative real-time PCR (qPCR) we assessed the effects of five-weeks of chronic unpredictable stress (CUS) exposure on the expression of GABA-synthesizing enzymes (GAD65 and GAD67), calcium-binding proteins (calbindin (CB), parvalbumin (PV) and calretinin (CR)), and neuropeptides co-expressed in GABAergic neurons (somatostatin (SST), neuropeptide Y (NPY), vasoactive intestinal peptide (VIP) and cholecystokinin (CCK)) in the prefrontal cortex (PFC) and hippocampus (HPC) of rats. We also investigated the effects of corticosterone (CORT) and dexamethasone (DEX) exposure on these markers in vitro in primary cortical and hippocampal cultures. We found that CUS induced significant reductions of GAD67 protein levels in both the PFC and HPC of CUS-exposed rats, but did not detect changes in GAD65 protein expression. Similar protein expression changes were found in vitro in cortical neurons. In addition, our results provide clear evidence of reduced markers of interneuron population(s), namely SST and NPY, in the PFC, suggesting these cell types may be selectively vulnerable to chronic stress. Together, this work highlights that chronic stress induces regional and cell type-selective effects on GABAergic interneurons in rats. These findings provide additional supporting evidence that stress-induced GABA neuron dysfunction and cell vulnerability play critical roles in the pathophysiology of stress-related illnesses, including major depressive disorder. PMID:28835932
Ailstock, M.S.; Fleming, W.J.; Cooke, T.J.
1991-01-01
Clonal lines of the submersed aquatic angiosperm Potamogeton pectinatus were grown in three culture systems. The first, which used sucrose as a carbon source in a liquid medium, supported vigorous vegetative growth and can be used to propagate large numbers of plants in axenic conditions. In this culture system, plants were responsive to increasing photosynthetically active radiation (PAR) photon flux density (PFD) and were photosynthetically competent. However, their growth was heterotrophic and root development was poor. When these plants were transferred to a second nonaxenic culture system, which used 16-l buckets containing artificial sediments and tap water, growth was autotrophic and plants were morphologically identical to field-harvested P. pectinatus. The last culture system which consisted of a sand substrate and inorganic nutrient bathing solution aerated with 135 ml min-1 ambient air enhanced to 3.0% CO2 was axenic and supported autotrophic growth by plants that were also morphologically normal.
Seawater-Cultured Botryococcus braunii for Efficient Hydrocarbon Extraction
Furuhashi, Kenichi; Saga, Kiyotaka; Okada, Shigeru; Imou, Kenji
2013-01-01
As a potential source of biofuel, the green colonial microalga Botryococcus braunii produces large amounts of hydrocarbons that are accumulated in the extracellular matrix. Generally, pretreatment such as drying or heating of wet algae is needed for sufficient recoveries of hydrocarbons from B. braunii using organic solvents. In this study, the Showa strain of B. braunii was cultured in media derived from the modified Chu13 medium by supplying artificial seawater, natural seawater, or NaCl. After a certain period of culture in the media with an osmotic pressure corresponding to 1/4-seawater, hydrocarbon recovery rates exceeding 90% were obtained by simply mixing intact wet algae with n-hexane without any pretreatments and the results using the present culture conditions indicate the potential for hydrocarbon milking. Highlights Seawater was used for efficient hydrocarbon extraction from Botryococcus braunii. The alga was cultured in media prepared with seawater or NaCl. Hydrocarbon recovery rate exceeding 90% was obtained without any pretreatment. PMID:23799107
Targońska, Katarzyna; Kucharczyk, Dariusz; Zarski, Daniel; Cejko, Beata Irena; Krejszeff, Sławomir; Kupren, Krzysztof; Król, Radosław; Dryl, Katarzyna; Kowalski, Radosław Kajetan; Glogowski, Jan
2011-09-01
The aim of this work was to compare the effects of controlled reproduction of cultured and wild common barbel, Barbus barbus (L.). Preparations containing different GnRH analogues and dopamine receptor antagonists (Ovopel, Ovaprim) as well as human chorionic gonadotropin (hCG) (in the case of cultured fish) were applied and their influence on ovulation, spermiation and quality of gametes obtained was determined. No differences in the qualitative or quantitative parameters of semen were found between fish stimulated with different hormonal preparations and those not receiving hormonal stimulation. The high suitability of Ovaprim for ovulation induction in (cultured and wild) barbel was confirmed. The highest synchronisation of ovulation was obtained after the application of Ovopel (18 ± 3 h), but the best results of controlled reproduction (expressed as the percentage of ovulations and survival of embryos) were obtained by applying Ovaprim (83.2 ± 4.1). A significantly higher percentage of ovulation was obtained in cultured fish (80-90%) than in wild fish (< 25%).
Egg-Independent Influenza Vaccines and Vaccine Candidates
Manini, Ilaria; Pozzi, Teresa; Rossi, Stefania; Montomoli, Emanuele
2017-01-01
Vaccination remains the principal way to control seasonal infections and is the most effective method of reducing influenza-associated morbidity and mortality. Since the 1940s, the main method of producing influenza vaccines has been an egg-based production process. However, in the event of a pandemic, this method has a significant limitation, as the time lag from strain isolation to final dose formulation and validation is six months. Indeed, production in eggs is a relatively slow process and production yields are both unpredictable and highly variable from strain to strain. In particular, if the next influenza pandemic were to arise from an avian influenza virus, and thus reduce the egg-laying hen population, there would be a shortage of embryonated eggs available for vaccine manufacturing. Although the production of egg-derived vaccines will continue, new technological developments have generated a cell-culture-based influenza vaccine and other more recent platforms, such as synthetic influenza vaccines. PMID:28718786
Dalgaard, Karen Marie; Thorsell, Georg; Delmar, Charlotte
2010-02-01
This article describes the significance of the identification and explicit communication of the different clinical phases in incurable illness trajectories in a hospital setting. The article is part of a qualitative study carried out in a Danish haematology department. The data were obtained through a total of 157 hours of participant observation and informal interviews with patients, families, doctors and nurses and four focus group interviews with doctors and nursing staff. Grounded theory was applied for the data analysis. The findings outline how the unpredictability of certain haematological malignancies and barriers in professional practice tended to postpone identifications of transitions between clinical phases. The study has identified ten barriers including personal, professional, time-related, cultural and organizational-for an open dialogue between staff, patients and families about illness progression. The quality of palliative care was affected as different clinical phases require different treatment and care strategies. Complex intervention is called for.
Damon, A
2000-12-01
The coffee berry borer, Hypothenemus hampei Ferrari, is a serious problem for the majority of the world's coffee growers and has proved to be one of the most intractable of present day pests. Despite a great deal of research, control still depends largely on the application of the organochlorine insecticide endosulfan, which is damaging to the environment, or a series of cultural and biological control methods which give variable and unpredictable results. This review summarizes the most important aspects of the biology and ecology of H. hampei and its control and identifies weak points in the knowledge about this pest. Emphasis is placed upon an analysis of the non-chemical control methods available and suggestions are offered for novel ecological and environmental factors worthy of further research, in the search for viable and sustainable control methods.
Facial Contrast Is a Cross-Cultural Cue for Perceiving Age
Porcheron, Aurélie; Mauger, Emmanuelle; Soppelsa, Frédérique; Liu, Yuli; Ge, Liezhong; Pascalis, Olivier; Russell, Richard; Morizot, Frédérique
2017-01-01
Age is a fundamental social dimension and a youthful appearance is of importance for many individuals, perhaps because it is a relevant predictor of aspects of health, facial attractiveness and general well-being. We recently showed that facial contrast—the color and luminance difference between facial features and the surrounding skin—is age-related and a cue to age perception of Caucasian women. Specifically, aspects of facial contrast decrease with age in Caucasian women, and Caucasian female faces with higher contrast look younger (Porcheron et al., 2013). Here we investigated faces of other ethnic groups and raters of other cultures to see whether facial contrast is a cross-cultural youth-related attribute. Using large sets of full face color photographs of Chinese, Latin American and black South African women aged 20–80, we measured the luminance and color contrast between the facial features (the eyes, the lips, and the brows) and the surrounding skin. Most aspects of facial contrast that were previously found to decrease with age in Caucasian women were also found to decrease with age in the other ethnic groups. Though the overall pattern of changes with age was common to all women, there were also some differences between the groups. In a separate study, individual faces of the 4 ethnic groups were perceived younger by French and Chinese participants when the aspects of facial contrast that vary with age in the majority of faces were artificially increased, but older when they were artificially decreased. Altogether these findings indicate that facial contrast is a cross-cultural cue to youthfulness. Because cosmetics were shown to enhance facial contrast, this work provides some support for the notion that a universal function of cosmetics is to make female faces look younger. PMID:28790941
Facial Contrast Is a Cross-Cultural Cue for Perceiving Age.
Porcheron, Aurélie; Mauger, Emmanuelle; Soppelsa, Frédérique; Liu, Yuli; Ge, Liezhong; Pascalis, Olivier; Russell, Richard; Morizot, Frédérique
2017-01-01
Age is a fundamental social dimension and a youthful appearance is of importance for many individuals, perhaps because it is a relevant predictor of aspects of health, facial attractiveness and general well-being. We recently showed that facial contrast-the color and luminance difference between facial features and the surrounding skin-is age-related and a cue to age perception of Caucasian women. Specifically, aspects of facial contrast decrease with age in Caucasian women, and Caucasian female faces with higher contrast look younger (Porcheron et al., 2013). Here we investigated faces of other ethnic groups and raters of other cultures to see whether facial contrast is a cross-cultural youth-related attribute. Using large sets of full face color photographs of Chinese, Latin American and black South African women aged 20-80, we measured the luminance and color contrast between the facial features (the eyes, the lips, and the brows) and the surrounding skin. Most aspects of facial contrast that were previously found to decrease with age in Caucasian women were also found to decrease with age in the other ethnic groups. Though the overall pattern of changes with age was common to all women, there were also some differences between the groups. In a separate study, individual faces of the 4 ethnic groups were perceived younger by French and Chinese participants when the aspects of facial contrast that vary with age in the majority of faces were artificially increased, but older when they were artificially decreased. Altogether these findings indicate that facial contrast is a cross-cultural cue to youthfulness. Because cosmetics were shown to enhance facial contrast, this work provides some support for the notion that a universal function of cosmetics is to make female faces look younger.
Ortakci, F; Sert, S
2012-12-01
The objective of this study was to determine the effect of encapsulation on survival of probiotic Lactobacillus acidophilus ATCC 4356 (ATCC 4356) in yogurt and during artificial gastric digestion. Strain ATCC 4356 was added to yogurt either encapsulated in calcium alginate or in free form (unencapsulated) at levels of 8.26 and 9.47 log cfu/g, respectively, and the influence of alginate capsules (1.5 to 2.5mm) on the sensorial characteristics of yogurts was investigated. The ATCC 4356 strain was introduced into an artificial gastric solution consisting of 0.08 N HCl (pH 1.5) containing 0.2% NaCl or into artificial bile juice consisting of 1.2% bile salts in de Man, Rogosa, and Sharpe broth to determine the stability of the probiotic bacteria. When incubated for 2h in artificial gastric juice, the free ATCC 4356 did not survive (reduction of >7 log cfu/g). We observed, however, greater survival of encapsulated ATCC 4356, with a reduction of only 3 log cfu/g. Incubation in artificial bile juice (6 h) did not significantly affect the viability of free or encapsulated ATCC 4356. Moreover, statistically significant reductions (~1 log cfu/g) of both free and encapsulated ATCC 4356 were observed during 4-wk refrigerated storage of yogurts. The addition of probiotic cultures in free or alginate-encapsulated form did not significantly affect appearance/color or flavor/odor of the yogurts. However, significant deficiencies were found in body/texture of yogurts containing encapsulated ATCC 4356. We concluded that incorporation of free and encapsulated probiotic bacteria did not substantially change the overall sensory properties of yogurts, and encapsulation in alginate using the extrusion method greatly enhanced the survival of probiotic bacteria against an artificial human gastric digestive system. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
The Disconnect between Theory and Practice in a Visual Culture Approach to Art Education
ERIC Educational Resources Information Center
Herrmann, Rebekka
2005-01-01
Issues of critical inquiry and social and environmental change have entered art education theory and are making their way into art classrooms. Unfortunately, rather than embracing how these ideas are carried out in the community of practicing artists and how they could be made relevant to students, many art teachers artificially force these ideas…
Artificially weathered crude oil was degraded by four diverse cultures of mixed marine bacteria under optimized conditions for 7 and 14 days. Loss in total weight of starting oil (30 g) ranged from 6.8-17.3% in biologically active incubations compared with only 0.9-1.1% in steril...
Production and early field performance of RPM® seedlings in Missouri floodplains
Daniel C. Dey; Wayne Lovelace; John M. Kabrick; Michael A. Gold
2004-01-01
A new nursery culture process has been developed to produce large container RPM? seedlings in an effort to improve the success in artificially regenerating hardwoods. Major features of the process include air root pruning of seedlings grown in a well aerated soil medium to encourage a dense, fibrous root system. Production has focused on native bottomland tree, shrub,...
Engineered Intrinsic Bioremediation of Ammonium Perchlorate in Groundwater
2010-12-01
German Collection of Microorganisms and Cell Cultures) GA Genetic Algorithms GA-ANN Genetic Algorithm Artificial Neural Network GMO genetically...for in situ treatment of perchlorate in groundwater. This is accomplished without the addition of genetically engineered microorganisms ( GMOs ) to the...perchlorate, even in the presence of oxygen and without the addition of genetically engineered microorganisms ( GMOs ) to the environment. This approach
Lovich, Jeffrey E.; Ennen, Joshua R.; Yackulic, Charles B.; Meyer-Wilkins, Kathie; Agha, Mickey; Loughran, Caleb L.; Bjurlin, Curtis; Austin, Meaghan; Madrak, Sheila V.
2015-01-01
Bet-hedging theory makes the counter-intuitive prediction that, if juvenile survival is low and unpredictable, organisms should consistently reduce short-term reproductive output to minimize the risk of reproductive failure in the long-term. We investigated the long-term reproductive output of an Agassiz's desert tortoise (Gopherus agassizii) population and conformance to a bet-hedging strategy of reproduction in an unpredictable but comparatively productive environment. Most females reproduced every year, even during periods of low precipitation and poor germination of food plants, and the mean percentage of reproducing females did not differ significantly on an annual basis. Although mean annual egg production (clutch size × clutch frequency) differed significantly among years, mean clutch size and mean clutch frequency remained relatively constant. During an El Niño year, mean annual egg production and mean annual clutch frequency were the highest ever reported for this species. Annual egg production was positively influenced by maternal body size but clutch size and clutch frequency were not. Our long-term results confirm earlier conclusions based on short-term research that desert tortoises have a bet-hedging strategy of producing small clutches almost every year. The risk of long-term reproductive failure is minimized in unpredictable environments, both through time by annually producing multiple small clutches over a long reproductive lifespan, even in years of low resource availability, and through space by depositing multiple annual clutches in different locations. The extraordinary annual reproductive output of this population appears to be the result of a typically high but unpredictable biomass of annual food plants at the site relative to tortoise habitat in dryer regions. Under the comparatively productive but unpredictable conditions, tortoises conform to predictions of a bet-hedging strategy of reproduction with relatively small but consistent clutch sizes.
Monsarrat, Sophie; Benhamou, Simon; Sarrazin, François; Bessa-Gomes, Carmen; Bouten, Willem; Duriez, Olivier
2013-01-01
Feeding stations are commonly used to sustain conservation programs of scavengers but their impact on behaviour is still debated. They increase the temporal and spatial predictability of food resources while scavengers have supposedly evolved to search for unpredictable resources. In the Grands Causses (France), a reintroduced population of Griffon vultures Gyps fulvus can find carcasses at three types of sites: 1. "light feeding stations", where farmers can drop carcasses at their farm (spatially predictable), 2. "heavy feeding stations", where carcasses from nearby farms are concentrated (spatially and temporally predictable) and 3. open grasslands, where resources are randomly distributed (unpredictable). The impact of feeding stations on vulture's foraging behaviour was investigated using 28 GPS-tracked vultures. The average home range size was maximal in spring (1272 ± 752 km(2)) and minimal in winter (473 ± 237 km(2)) and was highly variable among individuals. Analyses of home range characteristics and feeding habitat selection via compositional analysis showed that feeding stations were always preferred compared to the rest of the habitat where vultures can find unpredictable resources. Feeding stations were particularly used when resources were scarce (summer) or when flight conditions were poor (winter), limiting long-ranging movements. However, when flight conditions were optimal, home ranges also encompassed large areas of grassland where vultures could find unpredictable resources, suggesting that vultures did not lose their natural ability to forage on unpredictable resources, even when feeding stations were available. However during seasons when food abundance and flight conditions were not limited, vultures seemed to favour light over heavy feeding stations, probably because of the reduced intraspecific competition and a pattern closer to the natural dispersion of resources in the landscape. Light feeding stations are interesting tools for managing food resources, but don't prevent vultures to feed at other places with possibly high risk of intoxication (poison).
Ethnomathematics elements in Batik Bali using backpropagation method
NASA Astrophysics Data System (ADS)
Lestari, Mei; Irawan, Ari; Rahayu, Wanti; Wayan Parwati, Ni
2018-05-01
Batik is one of traditional arts that has been established by the UNESCO as Indonesia’s cultural heritage. Batik has varieties and motifs, and each motifs has its own uniqueness but seems similar, that makes it difficult to identify. This study aims to develop an application that can identify typical batik Bali with etnomatematics elements on it. Etnomatematics is a study that shows relation between culture and mathematics concepts. Etnomatematics in Batik Bali is more to geometrical concept in line of strong Balinese culture element. The identification process is use backpropagation method. Steps of backpropagation methods are image processing (including scalling and tresholding image process). Next step is insert the processed image to an artificial neural network. This study resulted an accuracy of identification of batik Bali that has Etnomatematics elements on it.
[Comparative studies of methods of salmonella enrichment (author's transl)].
Pietzsch, O; Kretschmer, F J; Bulling, E
1975-07-01
Eight different methods of salmonella enrichment were compared in two series of experiments involving 100 samples of whole-egg powder and 80 samples of frozen whole liquid egg, respectively. 66 out of a total of 100 samples of whole-egg powder had been artificially infected with varying numbers of S. typhi-murium; 60 out of 80 samples of frozen whole liquid egg were found to be naturally infected with various salmonella species. 3 of the 8 methods (Table 1) were compared within an international collaborative study with 14 laboratories in 11 countries participating. A reduction of the pre-enrichment period from 18 to 6 hours and of volumes used in pre-enrichment and selective enrichment from 10 and 100 ml, respectively to 1 and 10 ml, respectively were found to have adverse influence upon the result of isolations, in particular in the case of weakly infected samples. In contrast, extended incubation over 48 hours as well as preparation of two sub-cultures on solid selective media following incubation of enrichment cultures over 18-24 hours and 42-48 hours, respectively always resulted in a certain increase of salmonella yield which, however, exhibited gradual differences for the individual methods examined. Preparation of a 2nd sub-culture meant, in particular, a decisive improvement of the result of isolations from artificially infected samples if selenite-cystine enrichment volumes were 10 and 100 ml, respectively. The best results could be obtained by means of the following methods of enrichment: Pre-enrichment of material in buffered peptone water at 37 degrees C over 18 hours; pipetting of 10 ml inoculated and incubated pre-enriched material into 100 ml selenite-cystine or tetrathionate enrichment medium according to MULLER-KAUFFMANN; onward incubation of the enrichment culture at 43 degrees C over 48 hours; and preparation of sub-cultures on solid selective media after 24 and 48 hours. The method using tetrathionate enrichment medium was found to be most expensive, results, however, were the most consistent ones.
Phenologic variation of major triterpenoids in regular and white Antrodia cinnamomea.
Chen, Wei-Lun; Ho, Yen-Peng; Chou, Jyh-Ching
2016-12-01
Antrodia cinnamomea and its host Cinnamomum kanehirae are both endemic species unique to Taiwan. Many studies have confirmed that A. cinnamomea is rich in polysaccharides and triterpenoids that may carry medicinal effects in anti-cancer, anti-inflammation, anti-hypertension, and anti-oxidation. Therefore it is of interest to study the chemical variation of regular orange-red strains and white strains, which included naturally occurring and blue-light induced white A. cinnamomea. The chemical profiles of A. cinnamomea extracts at different growth stages were compared using thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). The TLC and HPLC profiles indicated that specific triterpenoids varied between white and regular strains. Moreover, the compounds of blue-light induced white strain were similar to those of naturally occurring white strain but retained specific chemical characteristics in more polar region of the HPLC chromatogram of regular strain. Blue-light radiation could change color of the regular A. cinnamomea from orange-red to white by changing its secondary metabolism and growth condition. Naturally occurring white strain did not show a significantly different composition of triterpenoid profiles up to eight weeks old when compared with the triterpenoid profiles of the regular strain at the same age. The ergostane-type triterpenoids were found existing in both young mycelia and old mycelia with fruiting body in artificial agar-plate medium culture, suggesting a more diversified biosynthetic pathway in artificial agar-plate culture rather than wild or submerged culture.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chigorno, V.; Cardace, G.; Pitto, M.
1986-03-01
A radiometric method for the assay of ganglioside sialidase in cultured human fibroblasts was set up. As substrate, highly radioactive (1.28 Ci/mmol) ganglioside GD/sub 1a/ isotopically tritium-labeled at carbon C-3 of the long chain base was employed; the liberated, and TLC separated (/sup 3/H)GM/sub 1/ was determined by computer-assisted radiochromatoscanning. Under experimental conditions that provided a low and quite acceptable (4-5%) coefficient of variation, the detection limit of the method was 0.1 nmol of liberated GM/sub 1/, using as low as 10 ..mu..g of fibroblast homogenate as protein. The detection limit could be lowered to 0.02-0.03 nmol, adopting conditions that,more » however, carried a higher analytical error (coefficient of variation over 10%). The content of ganglioside sialidase in human fibroblasts cultured in 75-cm/sup 2/ plastic flasks was 5.8 -/+ 2.5 (SD) nmol liberated GM/sub 1/ h/sup -1/ mg protein/sup -1/. Subfractionation studies performed on fibroblast homogenate showed that the ganglioside sialidase was mainly associated with the light membrane subfraction that was rich in plasma and intracellular membranes. This subfraction displayed almost no sialidase activity on the artificial substrate 4-methylumbelliferyl-D-N-acetylneuraminic acid. A small but measurable ganglioside sialidase activity was also present in the lysosome-enriched subfraction, which contained a very high sialidase activity on the above artificial substrate.« less
Animal social networks as substrate for cultural behavioural diversity.
Whitehead, Hal; Lusseau, David
2012-02-07
We used individual-based stochastic models to examine how social structure influences the diversity of socially learned behaviour within a non-human population. For continuous behavioural variables we modelled three forms of dyadic social learning, averaging the behavioural value of the two individuals, random transfer of information from one individual to the other, and directional transfer from the individual with highest behavioural value to the other. Learning had potential error. We also examined the transfer of categorical behaviour between individuals with random directionality and two forms of error, the adoption of a randomly chosen existing behavioural category or the innovation of a new type of behaviour. In populations without social structuring the diversity of culturally transmitted behaviour increased with learning error and population size. When the populations were structured socially either by making individuals members of permanent social units or by giving them overlapping ranges, behavioural diversity increased with network modularity under all scenarios, although the proportional increase varied considerably between continuous and categorical behaviour, with transmission mechanism, and population size. Although functions of the form e(c)¹(m)⁻(c)² + (c)³(Log(N)) predicted the mean increase in diversity with modularity (m) and population size (N), behavioural diversity could be highly unpredictable both between simulations with the same set of parameters, and within runs. Errors in social learning and social structuring generally promote behavioural diversity. Consequently, social learning may be considered to produce culture in populations whose social structure is sufficiently modular. Copyright © 2011 Elsevier Ltd. All rights reserved.
Beard, Renée L
2008-03-01
Clinicians aim to establish trust during medical encounters because, without it, health consumers may not seek medical care, consider their diagnoses legitimate, or adhere to treatment regimens. This paper examines the identification and treatment of memory loss within two specialty clinics to understand how cultural dynamics, such as organizational ethos and work practices, influence the social fabric of cognitive evaluations. Ethnographic data suggest important historical and cultural differences in the approaches to Alzheimer's disease (AD). Organizational routines, however, support a common goal, that of moving individuals from "potential patients" to patients, and ultimately research subjects, through establishing trust. Although the processes through which trust is potentially achieved, or the social conditions of trust, were similar at the sites, the object of trust was different. Whereas one clinic encouraged trust in collective medical expertise, the other focused on trust in specific clinicians. These conditions affect the clinical consequences of trust, particularly how and when the diagnosis is delivered, use of the AD label and other terminology, and the level of standardization. The individual consequences include perceptions of patients and depictions of the prognosis. Whether cognitive impairment is viewed as a scientific puzzle to be solved or is seen as a chronic illness significantly shapes the organizational processes of clinical evaluation. Alzheimer's disease, as a cultural object, is a particularly salient exemplar of the clinical negotiation of ambiguous diagnostic categorizations and the unpredictable patient in daily biomedical practice.
Kohlen, Helen
2015-07-01
In this article, Hannah Arendt's concept of action will be used to problematize current transformations of the health care sector and examine some responses by ethicists in light of those transformations. The sphere of human interaction that should typify health care work is identified as an action of unpredictable praxis in contrast to controllable procedures and techniques which increasingly take place in the health care sector. © 2015 John Wiley & Sons Ltd.
Fragmentation and Unpredictability of Early-Life Experience in Mental Disorders
Baram, Tallie Z.; Solodkin, Ana; Davis, Elysia P.; Stern, Hal; Obenaus, Andre; Sandman, Curt A.; Small, Steven L.
2012-01-01
Maternal sensory signals in early life play a crucial role in programming the structure and function of the developing brain, promoting vulnerability or resilience to emotional and cognitive disorders. In rodent models of early-life stress, fragmentation and unpredictability of maternally derived sensory signals provoke persistent cognitive and emotional dysfunction in offspring. Similar variability and inconsistency of maternal signals during both gestation and early postnatal human life may influence development of emotional and cognitive functions, including those that underlie later depression and anxiety. PMID:22885631
1985-01-01
Copyright by Bruce D. Duniouchel 1985 I- e Ie ACKNOWLEDGMENTS No project as involved and complex as the present investigation could L be accomplished...unpredictable because of the great complexity of the forces surrounding him. When the event is interpreted in this way by an individual, we have labeled...the result of luck, chance, fate, under the control of powerful others, or is unpredictable because of the great complexity of forces surrounding him
Li, Tianlong; Chang, Xiaocong; Wu, Zhiguang; Li, Jinxing; Shao, Guangbin; Deng, Xinghong; Qiu, Jianbin; Guo, Bin; Zhang, Guangyu; He, Qiang; Li, Longqiu; Wang, Joseph
2017-09-26
Self-propelled micro- and nanoscale robots represent a rapidly emerging and fascinating robotics research area. However, designing autonomous and adaptive control systems for operating micro/nanorobotics in complex and dynamically changing environments, which is a highly demanding feature, is still an unmet challenge. Here we describe a smart microvehicle for precise autonomous navigation in complicated environments and traffic scenarios. The fully autonomous navigation system of the smart microvehicle is composed of a microscope-coupled CCD camera, an artificial intelligence planner, and a magnetic field generator. The microscope-coupled CCD camera provides real-time localization of the chemically powered Janus microsphere vehicle and environmental detection for path planning to generate optimal collision-free routes, while the moving direction of the microrobot toward a reference position is determined by the external electromagnetic torque. Real-time object detection offers adaptive path planning in response to dynamically changing environments. We demonstrate that the autonomous navigation system can guide the vehicle movement in complex patterns, in the presence of dynamically changing obstacles, and in complex biological environments. Such a navigation system for micro/nanoscale vehicles, relying on vision-based close-loop control and path planning, is highly promising for their autonomous operation in complex dynamic settings and unpredictable scenarios expected in a variety of realistic nanoscale scenarios.
Soils: man-caused radioactivity and radiation forecast
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gablin, Vassily
2007-07-01
Available in abstract form only. Full text of publication follows: One of the main tasks of the radiation safety guarantee is non-admission of the excess over critical radiation levels. In Russia they are man-caused radiation levels. Meanwhile any radiation measurement represents total radioactivity. That is why it is hard to assess natural and man-caused contributions to total radioactivity. It is shown that soil radioactivity depends on natural factors including radioactivity of rocks and cosmic radiation as well as man-caused factors including nuclear and non-nuclear technologies. Whole totality of these factors includes unpredictable (non-deterministic) factors - nuclear explosions and radiation accidents,more » and predictable ones (deterministic) - all the rest. Deterministic factors represent background radioactivity whose trends is the base of the radiation forecast. Non-deterministic factors represent man-caused radiation treatment contribution which is to be controlled. This contribution is equal to the difference in measured radioactivity and radiation background. The way of calculation of background radioactivity is proposed. Contemporary soils are complicated technologically influenced systems with multi-leveled spatial and temporary inhomogeneity of radionuclides distribution. Generally analysis area can be characterized by any set of factors of soil radioactivity including natural and man-caused factors. Natural factors are cosmic radiation and radioactivity of rocks. Man-caused factors are shown on Fig. 1. It is obvious that man-caused radioactivity is due to both artificial and natural emitters. Any result of radiation measurement represents total radioactivity i.e. the sum of activities resulting from natural and man-caused emitters. There is no gauge which could separately measure natural and man-caused radioactivity. That is why it is so hard to assess natural and man-caused contributions to soil radioactivity. It would have been possible if human activity had led to contamination of soil only by artificial radionuclides. But we can view a totality of soil radioactivity factors in the following way. (author)« less
Measurement and reconstruction of the leaflet geometry for a pericardial artificial heart valve.
Jiang, Hongjun; Campbell, Gord; Xi, Fengfeng
2005-03-01
This paper describes the measurement and reconstruction of the leaflet geometry for a pericardial heart valve. Tasks involved include mapping the leaflet geometries by laser digitizing and reconstructing the 3D freeform leaflet surface based on a laser scanned profile. The challenge is to design a prosthetic valve that maximizes the benefits offered to the recipient as compared to the normally operating naturally-occurring valve. This research was prompted by the fact that artificial heart valve bioprostheses do not provide long life durability comparable to the natural heart valve, together with the anticipated benefits associated with defining the valve geometries, especially the leaflet geometries for the bioprosthetic and human valves, in order to create a replicate valve fabricated from synthetic materials. Our method applies the concept of reverse engineering in order to reconstruct the freeform surface geometry. A Brown & Shape coordinate measuring machine (CMM) equipped with a HyMARC laser-digitizing system was used to measure the leaflet profiles of a Baxter Carpentier-Edwards pericardial heart valve. The computer software, Polyworks was used to pre-process the raw data obtained from the scanning, which included merging images, eliminating duplicate points, and adding interpolated points. Three methods, creating a mesh model from cloud points, creating a freeform surface from cloud points, and generating a freeform surface by B-splines are presented in this paper to reconstruct the freeform leaflet surface. The mesh model created using Polyworks can be used for rapid prototyping and visualization. To fit a freeform surface to cloud points is straightforward but the rendering of a smooth surface is usually unpredictable. A surface fitted by a group of B-splines fitted to cloud points was found to be much smoother. This method offers the possibility of manually adjusting the surface curvature, locally. However, the process is complex and requires additional manipulation. Finally, this paper presents a reverse engineered design for the pericardial heart valve which contains three identical leaflets with reconstructed geometry.
Artificial reproduction of two different spawn-forms of the chub.
Krejszeff, Sławomir; Targońska, Katarzyna; Zarski, Daniel; Kucharczyk, Dariusz
2010-03-01
The aim of this study was to compare, under controlled conditions, reproduction results of cultured and wild stock of the chub. Wild fish spawned only once a season whereas the cultured stock spawned at least two times. In the multiple-spawn stock, fewer fish spawned and the weight of produced oocytes was reduced compared to the single-spawn stock. Larvae obtained from the multi-spawn forms were smaller than those of the single-spawn stock. The occurrence of one species with two forms of spawning performance in the same area makes it difficult to develop an efficient method for controlling the reproduction.
Long, Marc; Paul-Pont, Ika; Hégaret, Hélène; Moriceau, Brivaela; Lambert, Christophe; Huvet, Arnaud; Soudant, Philippe
2017-09-01
To understand the fate and impacts of microplastics (MP) in the marine ecosystems, it is essential to investigate their interactions with phytoplankton as these may affect MP bioavailability to marine organisms as well as their fate in the water column. However, the behaviour of MP with marine phytoplanktonic cells remains little studied and thus unpredictable. The present study assessed the potential for phytoplankton cells to form hetero-aggregates with small micro-polystyrene (micro-PS) particles depending on microalgal species and physiological status. A prymnesiophycea, Tisochrysis lutea, a dinoflagellate, Heterocapsa triquetra, and a diatom, Chaetoceros neogracile, were exposed to micro-PS (2 μm diameter; 3.96 μg L -1 ) during their growth culture cycles. Micro-PS were quantified using an innovative flow-cytometry approach, which allowed the monitoring of the micro-PS repartition in microalgal cultures and the distinction between free suspended micro-PS and hetero-aggregates of micro-PS and microalgae. Hetero-aggregation was observed for C. neogracile during the stationary growth phase. The highest levels of micro-PS were "lost" from solution, sticking to flasks, with T. lutea and H. triquetra cultures. This loss of micro-PS sticking to the flask walls increased with the age of the culture for both species. No effects of micro-PS were observed on microalgal physiology in terms of growth and chlorophyll fluorescence. Overall, these results highlight the potential for single phytoplankton cells and residual organic matter to interact with microplastics, and thus potentially influence their distribution and bioavailability in experimental systems and the water column. Copyright © 2017 Elsevier Ltd. All rights reserved.
Schmitz, Anja; Grillon, Christian
2012-01-01
The threat of predictable and unpredictable aversive events was developed to assess short-duration (fear) and long-duration (anxiety) aversive states in humans. A typical experiment consists of three conditions: a safe condition (neutral (N)), during which participants are safe from aversive stimuli, and two threat conditions—one in which aversive events are administered predictably (P) (i.e., signaled by a threat cue), and one in which aversive stimuli are administered unpredictably (U). During the so-called NPU -threat test, ongoing change in aversive states is measured with the startle reflex. The NPU -threat test has been validated in pharmacological and clinical studies and can be implemented in children and adults. Similar procedures have been applied in animal models, making the NPU -threat test an ideal tool for translational research. The procedure is relatively short (35 min), simple to implement and generates consistent results with large effect sizes. PMID:22362158
Normative evidence accumulation in unpredictable environments
Glaze, Christopher M; Kable, Joseph W; Gold, Joshua I
2015-01-01
In our dynamic world, decisions about noisy stimuli can require temporal accumulation of evidence to identify steady signals, differentiation to detect unpredictable changes in those signals, or both. Normative models can account for learning in these environments but have not yet been applied to faster decision processes. We present a novel, normative formulation of adaptive learning models that forms decisions by acting as a leaky accumulator with non-absorbing bounds. These dynamics, derived for both discrete and continuous cases, depend on the expected rate of change of the statistics of the evidence and balance signal identification and change detection. We found that, for two different tasks, human subjects learned these expectations, albeit imperfectly, then used them to make decisions in accordance with the normative model. The results represent a unified, empirically supported account of decision-making in unpredictable environments that provides new insights into the expectation-driven dynamics of the underlying neural signals. DOI: http://dx.doi.org/10.7554/eLife.08825.001 PMID:26322383
Children reading spoken words: interactions between vocabulary and orthographic expectancy.
Wegener, Signy; Wang, Hua-Chen; de Lissa, Peter; Robidoux, Serje; Nation, Kate; Castles, Anne
2018-05-01
There is an established association between children's oral vocabulary and their word reading but its basis is not well understood. Here, we present evidence from eye movements for a novel mechanism underlying this association. Two groups of 18 Grade 4 children received oral vocabulary training on one set of 16 novel words (e.g., 'nesh', 'coib'), but no training on another set. The words were assigned spellings that were either predictable from phonology (e.g., nesh) or unpredictable (e.g., koyb). These were subsequently shown in print, embedded in sentences. Reading times were shorter for orally familiar than unfamiliar items, and for words with predictable than unpredictable spellings but, importantly, there was an interaction between the two: children demonstrated a larger benefit of oral familiarity for predictable than for unpredictable items. These findings indicate that children form initial orthographic expectations about spoken words before first seeing them in print. A video abstract of this article can be viewed at: https://youtu.be/jvpJwpKMM3E. © 2017 John Wiley & Sons Ltd.
Performance improvement of ERP-based brain-computer interface via varied geometric patterns.
Ma, Zheng; Qiu, Tianshuang
2017-12-01
Recently, many studies have been focusing on optimizing the stimulus of an event-related potential (ERP)-based brain-computer interface (BCI). However, little is known about the effectiveness when increasing the stimulus unpredictability. We investigated a new stimulus type of varied geometric pattern where both complexity and unpredictability of the stimulus are increased. The proposed and classical paradigms were compared in within-subject experiments with 16 healthy participants. Results showed that the BCI performance was significantly improved for the proposed paradigm, with an average online written symbol rate increasing by 138% comparing with that of the classical paradigm. Amplitudes of primary ERP components, such as N1, P2a, P2b, N2, were also found to be significantly enhanced with the proposed paradigm. In this paper, a novel ERP BCI paradigm with a new stimulus type of varied geometric pattern is proposed. By jointly increasing the complexity and unpredictability of the stimulus, the performance of an ERP BCI could be considerably improved.
Integration of animal behaviors under stresses with different time courses
Zheng, Lun; Zheng, Xigeng
2014-01-01
We used animal models of “forced swim stress” and “chronic unpredictable stress”, and tried to reveal whether a passive coping style of high flotation behavior in forced swim stress predicts anhedonia behavior after chronic unpredictable stress, and whether the dopamine system regulates floating and anhedonia behaviors. Our results confirmed that depression-prone rats use “floating behavior” as a coping strategy in forced swim stress and more readily suffer from anhedonia during chronic unpredictable stress. Intraperitoneal injection or nucleus accumbens microinjection of the dopamine 2/3 receptor subtype agonist ropinirole reduced floating behaviors in depression-prone animals, but increased sucrose preference in rats showing anhedonia. These data indicate that floating behavior is a defensive mode that is preferred by susceptible individuals under conditions of acute stress. Simultaneously, these animals more readily experienced anhedonia under long-term stress; that is, they were more readily affected by depression. Our results suggest that dopamine 2/3 receptor subtypes in the nucleus accumbens play an important role in floating behaviors and anhedonia. PMID:25317159
Rapid diagnosis of primary ciliary dyskinesia: cell culture and soft computing analysis.
Pifferi, Massimo; Bush, Andrew; Montemurro, Francesca; Pioggia, Giovanni; Piras, Martina; Tartarisco, Gennaro; Di Cicco, Maria; Chinellato, Iolanda; Cangiotti, Angela M; Boner, Attilio L
2013-04-01
Diagnosis of primary ciliary dyskinesia (PCD) sometimes requires repeated nasal brushing to exclude secondary ciliary alterations. Our aim was to evaluate whether the use of a new method of nasal epithelial cell culture can speed PCD diagnosis in doubtful cases and to identify which are the most informative parameters by means of a multilayer artificial neural network (ANN). A cross-sectional study was performed in patients with suspected PCD. All patients underwent nasal brushing for ciliary motion analysis, ultrastructural assessment and evaluation of ciliary function after ciliogenesis in culture by ANN. 151 subjects were studied. A diagnostic suspension cell culture was obtained in 117 nasal brushings. A diagnosis of PCD was made in 36 subjects (29 of whom were children). In nine out of the 36 patients the diagnosis was made only after a second brushing, because of equivocal results of both tests at first examination. In each of these subjects diagnosis of PCD was confirmed by cell culture results. Cell culture in suspension evaluated by means of ANN allows the separation of PCD from secondary ciliary dyskinesia patients after only 5 days of culture and allows diagnosis to be reached in doubtful cases, thus avoiding the necessity of a second sample.
NASA Astrophysics Data System (ADS)
Contessi, M.; Cantelli, L.; Fanti, F.; Gabbianelli, G.; Mohsen, H.
2012-04-01
National Geoparks initiatives are essential strategies to enhance the value of Earth's heritage and to promote a regional sustainable socio-economic and cultural development. As an example for geological heritage development, an ongoing partnership between the Department of Geological and Environmental Sciences of the University of Bologna (Italy) and the Office Nationales des Mines (Tunisia) attempt to ensure divulgation and preservation of the geological, geomorphological and archeological values of the Tataouine region in South Tunisia, with the final goal to create a Geopark. In this region, different environmental and cultural heritages that comprehend paleontology, geomorphology, stratigraphy and archeology coexist. Mesozoic beds that crop out extensively in the Tataouine region known since the beginning of the 20th century as Continental Intercalaire, yield numerous dinosaur and other vertebrate remains as well as tracksites. Moreover these Mesozoic deposits have been intensively modified for centuries by the local populations who created complex systems of artificial terraces, called jessour, in order to retain rainwater in the arid Tunisian climate and to exploit the scarce farm soil. These human artifacts deeply modified the morphological and hydrogeological landscape and created a unique cultural value that need to be preserved. From the perspective of science and conservation, a well-documented geological inventory of the fossiliferous sites has been produced and will be available as an electronic database. In particular, the Beni Ghedir valley, near the Goumrassene village, has been chosen has the main Geopark location as it includes, in a restricted area, a perfect example of jessour artifacts together with some well-preserved Ksour (ancient storage structures) and nicely preserved fossil sites. An interactive map of the artificial terrances has been produced using the ArcGis technology, in order to highlight the connection between the valley morphology, the jessour systems and the hydrologic framework. Concluding, we believe in the importance of the preservation of geological and cultural diversity and the need to establish international collaborations in order to assist the national and regional experts to fully understood and protect the Tunisian sites, as economic and cultural development of the country.
Hendrickx, Larissa; De Wever, Heleen; Hermans, Veronik; Mastroleo, Felice; Morin, Nicolas; Wilmotte, Annick; Janssen, Paul; Mergeay, Max
2006-01-01
MELiSSA is a bioregenerative life support system designed by the European Space Agency (ESA) for the complete recycling of gas, liquid and solid wastes during long distance space exploration. The system uses the combined activity of different living organisms: microbial cultures in bioreactors, a plant compartment and a human crew. In this minireview, the development of a short-cut ecological system for the biotransformation of organic waste is discussed from a microorganism's perspective. The artificial ecological model--still in full development--that is inspired by Earth's own geomicrobiological ecosystem serves as an ideal study object on microbial ecology and will become an indispensable travel companion in manned space exploration.
Mars Greenhouses: Concepts and Challenges. Proceedings from a 1999 Workshop
NASA Technical Reports Server (NTRS)
Wheeler, Ray M. (Editor); Martin-Brennan, Cindy (Editor)
2000-01-01
Topic covered include :Plants on Mars: On the Next Mission and in the Long Term Future; Bubbles in the Rocks: Natural and Artificial Caves and Cavities as Like Support Structures; Challenges for Bioregenerative Life Support on Mars; Cost Effectiveness Issues; Low Pressure Systems for Plant Growth; Plant Responses to Rarified Atmospheres; Can CO2 be Used as a Pressurizing Gas for Mars Greenhouses?; Inflatable Habitats Technology Development; Development of an Inflatable Greenhouse for a Modular Crop Production System; Mars Inflatable Greenhouse Workshop; Design Needs for Mars Deployable Greenhouse; Preliminary Estimates of the Possibilities for Developing a Deployable Greenhouse for a Planetary Surface Mars; Low Pressure Greenhouse Concepts for Mars; Mars Greenhouse Study: Natural vs. Artificial Lighting; and Wire Culture for an Inflatable Mars Greenhouse and Other Future Inflatable Space Growth Chambers.
Photosynthesis under artificial light: the shift in primary and secondary metabolism
Darko, Eva; Heydarizadeh, Parisa; Schoefs, Benoît; Sabzalian, Mohammad R.
2014-01-01
Providing an adequate quantity and quality of food for the escalating human population under changing climatic conditions is currently a great challenge. In outdoor cultures, sunlight provides energy (through photosynthesis) for photosynthetic organisms. They also use light quality to sense and respond to their environment. To increase the production capacity, controlled growing systems using artificial lighting have been taken into consideration. Recent development of light-emitting diode (LED) technologies presents an enormous potential for improving plant growth and making systems more sustainable. This review uses selected examples to show how LED can mimic natural light to ensure the growth and development of photosynthetic organisms, and how changes in intensity and wavelength can manipulate the plant metabolism with the aim to produce functionalized foods. PMID:24591723
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stevens, A.R.; Tyndall, R.L.; Coutant, C.C.
1977-12-01
To determine whether artificial heating of water by power plant discharges facilitates proliferation of the pathogenic free-living amoebae that cause primary amoebic meningoencephalitis, water samples (250 ml) were taken from discharges within 3,000 feet (ca. 914.4 m) of power plants and were processed for amoeba culture. Pathogenic Naegleria fowleri grew out of water samples from two of five lakes and rivers in Florida and from one of eight man-made lakes in Texas. Pathogenic N. fowleri did not grow from water samples taken from cooling towers and control lakes, the latter of which had no associated power plants. The identification ofmore » N. fowleri was confirmed by pathogenicity in mice and by indirect immunofluorescence analyses, by using a specific antiserum.« less
A standardized method of propagating the marine fish parasite, Amyloodinium ocellatum.
Bower, C E; Turner, D T; Biever, R C
1987-02-01
The peridinian dinoflagellate Amyloodinium ocellatum was propagated by serial passage in clownfish (Amphiprion ocellaris) and hybrid striped bass (Morone chrysops X Morone saxatilis). Each 25-50-mm fish was exposed to 4,000-6,000 dinospores in 400 ml of artificial seawater for 30 min. Two days after exposure, trophonts were harvested by immersing the fishes in fresh water. After encystment, tomonts were axenized by multiple washes with sterile distilled water and sterile artificial seawater containing penicillin and streptomycin, and then incubated in the antibiotic solution. High yields of both tomonts and dinospores of the same sizes and ages were obtained, and host mortalities were eliminated. Microbial growth in incubating cultures was inhibited until after dinospores had emerged from tomonts, and dinospores remained infective for at least 4 days at 26 C.
Application of cell co-culture system to study fat and muscle cells.
Pandurangan, Muthuraman; Hwang, Inho
2014-09-01
Animal cell culture is a highly complex process, in which cells are grown under specific conditions. The growth and development of these cells is a highly unnatural process in vitro condition. Cells are removed from animal tissues and artificially cultured in various culture vessels. Vitamins, minerals, and serum growth factors are supplied to maintain cell viability. Obtaining result homogeneity of in vitro and in vivo experiments is rare, because their structure and function are different. Living tissues have highly ordered complex architecture and are three-dimensional (3D) in structure. The interaction between adjacent cell types is quite distinct from the in vitro cell culture, which is usually two-dimensional (2D). Co-culture systems are studied to analyze the interactions between the two different cell types. The muscle and fat co-culture system is useful in addressing several questions related to muscle modeling, muscle degeneration, apoptosis, and muscle regeneration. Co-culture of C2C12 and 3T3-L1 cells could be a useful diagnostic tool to understand the muscle and fat formation in animals. Even though, co-culture systems have certain limitations, they provide a more realistic 3D view and information than the individual cell culture system. It is suggested that co-culture systems are useful in evaluating the intercellular communication and composition of two different cell types.
Worthington, Amber K; Parrott, Roxanne L; Smith, Rachel A
2018-04-01
A growing number of genetic tests are included in diagnostic protocols associated with many common conditions. A positive diagnosis associated with the presence of some gene versions in many instances predicts a range of possible outcomes, and the uncertainty linked to such results contributes to the need to understand varied responses and plan strategic communication. Uncertainty in illness theory (UIT; Mishel, 1988, 1990) guided the investigation of efforts to feel in control and hopeful regarding genetic testing and diagnosis for alpha-1 antitrypsin deficiency (AATD). Participants included 137 individuals with AATD recruited from the Alpha-1 Research Registry who were surveyed about their subjective numeracy, anxiety about math, spirituality, perceptions of illness unpredictability, negative affect regarding genetic testing, and coping strategies about a diagnosis. Results revealed that experiencing more fear and worry contributed both directly and indirectly to affect-management coping strategies, operating through individual perceptions of illness unpredictability. The inability to predict the symptoms and course of events related to a genetic illness and anxiety regarding math heightened fear and worry. Spirituality lessened both illness unpredictability and negative affective responses to a diagnosis. Results affirm the importance of clinician and counselor efforts to incorporate attention to patient spirituality. They also illustrate the complexity associated with strategic efforts to plan communication about the different versions of a gene's effects on well-being, when some versions align with mild health effects and others with severe effects.
To Switch or Not to Switch: Role of Cognitive Control in Working Memory Training in Older Adults.
Basak, Chandramallika; O'Connell, Margaret A
2016-01-01
It is currently not known what are the best working memory training strategies to offset the age-related declines in fluid cognitive abilities. In this randomized clinical double-blind trial, older adults were randomly assigned to one of two types of working memory training - one group was trained on a predictable memory updating task (PT) and another group was trained on a novel, unpredictable memory updating task (UT). Unpredictable memory updating, compared to predictable, requires greater demands on cognitive control (Basak and Verhaeghen, 2011a). Therefore, the current study allowed us to evaluate the role of cognitive control in working memory training. All participants were assessed on a set of near and far transfer tasks at three different testing sessions - before training, immediately after the training, and 1.5 months after completing the training. Additionally, individual learning rates for a comparison working memory task (performed by both groups) and the trained task were computed. Training on unpredictable memory updating, compared to predictable, significantly enhanced performance on a measure of episodic memory, immediately after the training. Moreover, individuals with faster learning rates showed greater gains in this episodic memory task and another new working memory task; this effect was specific to UT. We propose that the unpredictable memory updating training, compared to predictable memory updating training, may a better strategy to improve selective cognitive abilities in older adults, and future studies could further investigate the role of cognitive control in working memory training.
Evaluation of a Real-Time PCR Kit for Detecting Escherichia coli O157 in Bovine Fecal Samples
Bono, James L.; Keen, James E.; Miller, Laura C.; Fox, James M.; Chitko-McKown, Carol G.; Heaton, Michael P.; Laegreid, William W.
2004-01-01
A commercially available real-time, rapid PCR test was evaluated for its ability to detect Escherichia coli O157. Both the sensitivity and specificity of the assay were 99% for isolates in pure culture. The assay detected 1 CFU of E. coli O157:H7 g−1 in artificially inoculated bovine feces following enrichment. PMID:15006817
Daniel C. Dey
1995-01-01
The artificial regeneration of red oak by planting or direct seeding is an important method for restoring oak in ecosystems where it has been lost as a result of past management practices. Planting and direct seeding can also be used to supplement natural oak regeneration and to ensure that sufficient oak reproduction is in place when overstories are removed through...
First step in developing a 3D biodegradable fibrin scaffold for an artificial ovary
2013-01-01
Background Although transplantation of cryopreserved ovarian tissue is a promising approach to restore fertility in cancer patients, it is not advisable for women at risk of ovarian involvement due to the threat of reintroducing malignant cells. The aim of this study was therefore to find an alternative for these patients by development of an artificial ovary. Methods For construction of the artificial ovary matrix, we used a central composite design to investigate nine combinations of fibrinogen (mg/ml) and thrombin (IU/mL) (F/T): F1/T4, F12.5/T1, F12.5/T20, F25/T0.1, F25/T4, F25/T500, F50/T1, F50/T20 and F100/T4. From the first qualitative analyses (handling and matrix size), five combinations (F12.5/T1, F25/T4, F50/T20, F50/T1 and F100/T4) yielded positive results. They were further evaluated in order to assess fibrin matrix degradation and homogeneous cell encapsulation (density), survival and proliferation (Ki67), and atresia (TUNEL) before and after 7 days of in vitro culture. To determine the best compromise between maximizing the dynamic density (Y1) and minimizing the apoptosis rate (Y2), we used the desirability function approach. Results Two combinations (F12.5/T1 and F25/T4) showed greater distribution of cells before in vitro culture, reproducible degradation of the fibrin network and adequate support for isolated human ovarian stromal cells, with a high proportion of Ki67-positive cells. SEM analysis revealed a network of fibers with regular pores and healthy stromal cells after in vitro culture with both F/T combinations. Conclusion This study reports two optimal F/T combinations that allow survival and proliferation of isolated human ovarian cells. Further studies are required to determine if such a scaffold will also be a suitable environment for isolated ovarian follicles. PMID:24274108
Furnham, Adrian; Raja, Nazia; Khan, Umar Ali
2008-06-30
This study aimed to compare British, British Pakistani and Native Pakistani (from Pakistan) medical students' beliefs about the manifestation, causes and cures of schizophrenia, prior to any psychiatric training. A total of 305 participants completed a questionnaire on general beliefs about people with schizophrenia, causal explanations concerning the aetiology of schizophrenia and the role of hospitals and society in treating people with schizophrenia. It was predicted that compared with the British and British Pakistanis, the Pakistanis would have more negative beliefs and attitudes, considering people with schizophrenia to be more dangerous and unpredictable; they were also expected to use more superstitious beliefs to explain the cause of schizophrenia and its symptoms; as well as believe more in seeking help from God and faith healers. There was strong evidence to suggest that Pakistanis possessed more negative beliefs and attitudes about people with schizophrenia, but there was no evidence to indicate that Pakistanis believed more in superstitious causal explanations. Pakistanis were more likely to consider seeking help from faith healers, but not God, compared with British Pakistanis and the British. Results confirm previous European-Asian difference in the understanding of the cause, manifestation and cure of schizophrenia. The impact of traditional and Western cultural influences on British Pakistanis is considered.
The fear gasping face as a threat display in a Melanesian society
Crivelli, Carlos; Jarillo, Sergio; Fernández-Dols, José-Miguel
2016-01-01
Theory and research show that humans attribute both emotions and intentions to others on the basis of facial behavior: A gasping face can be seen as showing “fear” and intent to submit. The assumption that such interpretations are pancultural derives largely from Western societies. Here, we report two studies conducted in an indigenous, small-scale Melanesian society with considerable cultural and visual isolation from the West: the Trobrianders of Papua New Guinea. Our multidisciplinary research team spoke the vernacular and had extensive prior fieldwork experience. In study 1, Trobriand adolescents were asked to attribute emotions, social motives, or both to a set of facial displays. Trobrianders showed a mixed and variable attribution pattern, although with much lower agreement than studies of Western samples. Remarkably, the gasping face (traditionally considered a display of fear and submission in the West) was consistently matched to two unpredicted categories: anger and threat. In study 2, adolescents were asked to select the face that was threatening; Trobrianders chose the “fear” gasping face whereas Spaniards chose an “angry” scowling face. Our findings, consistent with functional approaches to animal communication and observations made on threat displays in small-scale societies, challenge the Western assumption that “fear” gasping faces uniformly express fear or signal submission across cultures. PMID:27791137
Martirosyan, Alina; Grintzalis, Konstantinos; Polet, Madeleine; Laloux, Laurie; Schneider, Yves-Jacques
2016-06-24
Interaction of nanoparticles with food matrix components may cause unpredictable health complications. Using an improved Caco-2 cell-based in vitro (co-)culture model the potential of quercetin as one of the major food flavonoids to alter the effect of silver nanoparticles (Ag-NPs) <20 nm in the human intestinal mucosa at real life concentrations was investigated. Ag-NPs (15-90 μg/ml) decreased cell viability and reduced thiol groups, induced oxidative/nitrosative stress and lipid peroxidation and led to activity changes of various antioxidant enzymes after 3h exposure. The contribution of Ag(+) ions within the concentrations released from nanoparticles was shown to be less important, compared to Ag-NPs. While leading to inflammatory response in the intestines, Ag-NPs, paradoxically, also showed a potential anti-infammatory effect manifested in down-regulated IL-8 levels. Quercetin, co-administered with Ag-NPs, led to a reduction of cytotoxicity, oxidative stress, and recovered metabolic activity of Caco-2 cells, suggesting the protective effects of this flavonoid against the harmful effect of Ag-NPs. Quercetin not only alleviated the effect of Ag-NPs on the gastrointestinal cells, but also demonstrated a potential to serve as a tool for reversible modulation of intestinal permeability. Copyright © 2016. Published by Elsevier Ireland Ltd.
A rural math, science, and technology elementary school tangled up in global networks of practice
NASA Astrophysics Data System (ADS)
Carlone, Heidi B.; Kimmel, Sue; Tschida, Christina
2010-06-01
This is an ethnographic study of a newly created math, science, and technology elementary magnet school in a rural community fiercely committed to cultural preservation while facing unprecedented economic instability brought on by massive loss of manufacturing jobs. Our goal was to understand global- and community-level contexts that influenced the school's science curriculum, the ways the school promoted itself to the community, and the implicit meanings of science held by school staff, parents and community members. Main sources of data were the county's newspaper articles from 2003 to 2006, the school's, town's, and business leaders' promotional materials, and interviews with school staff, parents, and community members. A key finding was the school's dual promotion of science education and character education. We make sense of this "science with character" curriculum by unpacking the school and community's entanglements with historical (cultural preservation), political (conservative politics, concerns for youth depravity), and economic (globalization) networks. We describe the ways those entanglements enabled certain reproductive meanings of school science (as add-on, suspect, and elitist) and other novel meanings of science (empathetic, nurturing, place-based). This study highlights the school as a site of struggle, entangled in multiple networks of practice that influence in positive, negative, and unpredictable ways, the enacted science curriculum.
Brief communication: Artificial cranial modification in Kow Swamp and Cohuna.
Durband, Arthur C
2014-09-01
The crania from Kow Swamp and Cohuna have been important for a number of debates in Australian paleoanthropology. These crania typically have long, flat foreheads that many workers have cited as evidence of genetic continuity with archaic Indonesian populations, particularly the Ngandong sample. Other scientists have alleged that at least some of the crania from Kow Swamp and the Cohuna skull have been altered through artificial modification, and that the flat foreheads possessed by these individuals are not phylogenetically informative. In this study, several Kow Swamp crania and Cohuna are compared to known modified and unmodified comparative samples. Canonical variates analyses and Mahalanobis distances are generated, and random expectation statistics are used to calculate statistical significance for these tests. The results of this study agree with prior work indicating that a portion of this sample shows evidence for artificial modification of the cranial vault. Many Kow Swamp crania and Cohuna display shape similarities with a population of known modified individuals from New Britain. Kow Swamp 1, 5, and Cohuna show the strongest evidence for modification, but other individuals from this sample also show evidence of culturally manipulated changes in cranial shape. This project provides added support for the argument that at least some Pleistocene Australian groups were practicing artificial cranial modification, and suggests that caution should be used when including these individuals in phylogenetic studies. Copyright © 2014 Wiley Periodicals, Inc.
Tran, Simon D; Sugito, Takayuki; Dipasquale, Giovanni; Cotrim, Ana P; Bandyopadhyay, Bidhan C; Riddle, Kathryn; Mooney, David; Kok, Marc R; Chiorini, John A; Baum, Bruce J
2006-10-01
There is no satisfactory conventional treatment for patients who experience irreversible salivary gland damage after therapeutic radiation for head and neck cancer or because of Sjögren's syndrome. Additionally, if most parenchyma is lost, these patients also are not candidates for evolving gene transfer strategies. To help such patients, several years ago we began to develop an artificial salivary gland. In the present study, we used a non-human primate tissue source, parotid glands from rhesus monkeys, to obtain potential autologous graft cells for development of a prototype device for in situ testing. Herein, we present 3 major findings. First, we show that primary cultures of rhesus parotid gland (RPG) cells are capable of attaining a polarized orientation, with Na(+)/K(+)-adenosine triphosphatase, zonula occludens-1, and claudin-1 distributed in specific domains appropriate for epithelial cells. Second, we show that RPG cells exhibit 2 essential epithelial functions required for graft cells in an artificial salivary gland device (i.e., an effective barrier to paracellular water flow and the generation of a moderate transepithelial electrical resistance). Third, we show that RPG cells can express functional water channels, capable of mediating directional fluid movement, after transduction by adenoviral and adeno-associated virus type 2 vectors. Together these results demonstrate that it is feasible to individually prepare RPG cells for eventual use in a prototype artificial salivary gland.
An approach to collective behavior in cell cultures: modeling and analysis of ECIS data
NASA Astrophysics Data System (ADS)
Rabson, David; Lafalce, Evan; Lovelady, Douglas; Lo, Chun-Min
2011-03-01
We review recent results in which statistical measures of noise in ECIS data distinguished healthy cell cultures from cancerous or poisoned ones: after subtracting the ``signal,'' the 1 /fα noise in the healthy cultures shows longer short-time and long-time correlations. We discuss application of an artificial neural network to detect the cancer signal, and we demonstrate a computational model of cell-cell communication that produces signals similar to those of the experimental data. The simulation is based on the q -state Potts model with inspiration from the Bak-Tang-Wiesenfeld sand-pile model. We view the level of organization larger than cells but smaller than organs or tissues as a kind of ``mesoscopic'' biological physics, in which few-body interactions dominate, and the experiments and computational model as ways of exploring this regime.
A kinetic modeling of chondrocyte culture for manufacture of tissue-engineered cartilage.
Kino-Oka, Masahiro; Maeda, Yoshikatsu; Yamamoto, Takeyuki; Sugawara, Katsura; Taya, Masahito
2005-03-01
For repairing articular cartilage defects, innovative techniques based on tissue engineering have been developed and are now entering into the practical stage of clinical application by means of grafting in vitro cultured products. A variety of natural and artificial materials available for scaffolds, which permit chondrocyte cells to aggregate, have been designed for their ability to promote cell growth and differentiation. From the viewpoint of the manufacturing process for tissue-engineered cartilage, the diverse nature of raw materials (seeding cells) and end products (cultured cartilage) oblige us to design a tailor-made process with less reproducibility, which is an obstacle to establishing a production doctrine based on bioengineering knowledge concerning growth kinetics and modeling as well as designs of bioreactors and culture operations for certification of high product quality. In this article, we review the recent advances in the manufacturing of tissue-engineered cartilage. After outlining the manufacturing processes for tissue-engineered cartilage in the first section, the second and third sections, respectively, describe the three-dimensional culture of chondrocytes with Aterocollagen gel and kinetic model consideration as a tool for evaluating this culture process. In the final section, culture strategy is discussed in terms of the combined processes of monolayer growth (ex vivo chondrocyte cell expansion) and three-dimensional growth (construction of cultured cartilage in the gel).
Survival of Campylobacter jejuni in naturally and artificially contaminated laying hen feces.
Ahmed, M F M; Schulz, J; Hartung, J
2013-02-01
Infected laying hens regularly excrete large amounts of Campylobacter jejuni with their feces, which represent a reservoir of infection within the flock and for animals in the region. However, the knowledge about survival times of C. jejuni in these feces is still scarce. Therefore, orienting laboratory experiments were carried out under controlled conditions to estimate the survival times of C. jejuni both in artificially and naturally contaminated laying hen feces. In 6 different laying hen flocks (3 Campylobacter-free and 3 Campylobacter-positive flocks), fresh excreta were randomly collected and pooled in 20-g samples per flock. In the laboratory, each of the 3 pooled samples from the Campylobacter-free barns were homogenized and mixed with 10 mL of a freshly prepared C. jejuni suspension (3 × 10(8) cfu/mL). The other 3 samples were homogenized only. The 6 samples were stored at 20 ± 1°C and 40 to 60% RH in 2 different incubators. Specimens of 2 g were taken from all 6 samples 1 h after storage and daily at the same time during the next 10 consecutive days and investigated on culturable C. jejuni. The survival times of culturable C. jejuni ranged from 72 to 96 h in artificially inoculated feces and varied from 120 to 144 h in naturally colonized flocks. The flaA typing by RFLP confirmed that the isolates from the artificially contaminated feces were identical with the added strain. A total of 5 different flaA types were identified from the naturally contaminated feces, and survival of these isolates was dependent on flaA type. The demonstrated survival times indicate that contaminated fresh feces are an important reservoir of C. jejuni, representing a permanent source of infection over at least 6 d after excretion. It shows the considerable potential of fresh feces in transmitting the agent within and between flocks during that period. This 6-d span should be considered when poultry manure is applied to land as organic fertilizer.
Cell Culturing of Cytoskeleton
NASA Technical Reports Server (NTRS)
2004-01-01
Biomedical research offers hope for a variety of medical problems, from diabetes to the replacement of damaged bone and tissues. Bioreactors, which are used to grow cells and tissue cultures, play a major role in such research and production efforts. Cell culturing, such as this bone cell culture, is an important part of biomedical research. The BioDyn payload includes a tissue engineering investigation. The commercial affiliate, Millenium Biologix, Inc., has been conducting bone implant experiments to better understand how synthetic bone can be used to treat bone-related illnesses and bone damaged in accidents. On STS-95, the BioDyn payload will include a bone cell culture aimed to help develop this commercial synthetic bone product. Millenium Biologix, Inc., is exploring the potential for making human bone implantable materials by seeding its proprietary artificial scaffold material with human bone cells. The product of this tissue engineering experiment using the Bioprocessing Modules (BPMs) on STS-95 is space-grown bone implants, which could have potential for dental implants, long bone grafts, and coating for orthopedic implants such as hip replacements.
Cell Culturing of Cytoskeleton
NASA Technical Reports Server (NTRS)
2004-01-01
Biomedical research offers hope for a variety of medical problems, from diabetes to the replacement of damaged bone and tissues. Bioreactors, which are used to grow cells and tissue cultures, play a major role in such research and production efforts. Cell culturing, such as this bone cell culture, is an important part of biomedical research. The BioDyn payload includes a tissue engineering investigation. The commercial affiliate, Millenium Biologix, Inc. has been conducting bone implant experiments to better understand how synthetic bone can be used to treat bone-related illnesses and bone damaged in accidents. On STS-95, the BioDyn payload will include a bone cell culture aimed to help develop this commercial synthetic bone product. Millenium Biologix, Inc. is exploring the potential for making human bone implantable materials by seeding its proprietary artificial scaffold material with human bone cells. The product of this tissue engineering experiment using the Bioprocessing Modules (BPMs) on STS-95 is space-grown bone implants, which could have potential for dental implants, long bone grafts, and coating for orthopedic implants such as hip replacements.
A preliminary study of the Caprella scaura amphipod culture for potential use in aquaculture
NASA Astrophysics Data System (ADS)
Baeza-Rojano, Elena; Calero-Cano, Sandra; Hachero-Cruzado, Ismael; Guerra-García, José Manuel
2013-10-01
The caprellid amphipod Caprella scaura Templeton, 1836 was investigated as a mass culture organism, for potential use as natural prey in aquaculture. C. scaura showed good population growth during 3 months of culturing with nauplii of Artemia sp. and microalgae as food source. A final mean population size of 12,510.67 individuals/tank and a maximum density of 10,460 individuals m- 2 were obtained; a 50-fold increase of the initial population was observed. Juveniles were the most abundant stage in the culture (86.0% of total), followed by mature females (5.4%) and immature males (3.1%). Three kinds of plastic mesh with different complexity levels were used as artificial substrates for amphipods to attach to and shelter. There were no significant differences in the total number of individuals present on each kind of mesh, although female and male adults were more abundant in folded meshes with larger pore diameter. This research demonstrated that the caprellid amphipod C. scaura may be readily cultured at high densities with a variety of mesh morphologies allowing more efficient use of tank volume and improved handling.
"Artificial micro organs"--a microfluidic device for dielectrophoretic assembly of liver sinusoids.
Schütte, Julia; Hagmeyer, Britta; Holzner, Felix; Kubon, Massimo; Werner, Simon; Freudigmann, Christian; Benz, Karin; Böttger, Jan; Gebhardt, Rolf; Becker, Holger; Stelzle, Martin
2011-06-01
In order to study possible toxic side effects of potential drug compounds in vitro a reliable test system is needed. Predicting liver toxicity presents a major challenge of particular importance as liver cells grown in a cell culture suffer from a rapid loss of their liver specific functions. Therefore we are developing a new microfluidic test system for liver toxicity. This test system is based on an organ-like liver 3D co-culture of hepatocytes and endothelial cells. We devised a microfluidic chip featuring cell culture chambers with integrated electrodes for the assembly of liver sinusoids by dielectrophoresis. Fluid channels enable an organ-like perfusion with culture media and test compounds. Different chamber designs were studied and optimized with regard to dielectrophoretic force distribution, hydrodynamic flow profile, and cell trapping rate using numeric simulations. Based on simulation results a microchip was injection-moulded from COP. This chip allowed the assembly of viable hepatocytes and endothelial cells in a sinusoid-like fashion.
2004-04-15
Biomedical research offers hope for a variety of medical problems, from diabetes to the replacement of damaged bone and tissues. Bioreactors, which are used to grow cells and tissue cultures, play a major role in such research and production efforts. Cell culturing, such as this bone cell culture, is an important part of biomedical research. The BioDyn payload includes a tissue engineering investigation. The commercial affiliate, Millenium Biologix, Inc., has been conducting bone implant experiments to better understand how synthetic bone can be used to treat bone-related illnesses and bone damaged in accidents. On STS-95, the BioDyn payload will include a bone cell culture aimed to help develop this commercial synthetic bone product. Millenium Biologix, Inc., is exploring the potential for making human bone implantable materials by seeding its proprietary artificial scaffold material with human bone cells. The product of this tissue engineering experiment using the Bioprocessing Modules (BPMs) on STS-95 is space-grown bone implants, which could have potential for dental implants, long bone grafts, and coating for orthopedic implants such as hip replacements.
2004-04-15
Biomedical research offers hope for a variety of medical problems, from diabetes to the replacement of damaged bone and tissues. Bioreactors, which are used to grow cells and tissue cultures, play a major role in such research and production efforts. Cell culturing, such as this bone cell culture, is an important part of biomedical research. The BioDyn payload includes a tissue engineering investigation. The commercial affiliate, Millenium Biologix, Inc. has been conducting bone implant experiments to better understand how synthetic bone can be used to treat bone-related illnesses and bone damaged in accidents. On STS-95, the BioDyn payload will include a bone cell culture aimed to help develop this commercial synthetic bone product. Millenium Biologix, Inc. is exploring the potential for making human bone implantable materials by seeding its proprietary artificial scaffold material with human bone cells. The product of this tissue engineering experiment using the Bioprocessing Modules (BPMs) on STS-95 is space-grown bone implants, which could have potential for dental implants, long bone grafts, and coating for orthopedic implants such as hip replacements.
Wójcik-Fatla, Angelina; Stojek, Nimfa Maria; Dutkiewicz, Jacek
2012-01-01
The aim of the present study was: - to compare methods for concentration and isolation of Legionella DNA from water; - to examine the efficacy of various modifications of PCR test (PCR, semi-nested PCR, and real-time PCR) for the detection of known numbers of Legionella pneumophila in water samples artificially contaminated with the strain of this bacterium and in randomly selected samples of environmental water, in parallel with examination by culture. It was found that filtration is much more effective than centrifugation for the concentration of DNA in water samples, and that the Qiamp DNA Mini-Kit is the most efficient for isolation of Legionella DNA from water. The semi-nested PCR and real-time PCR proved to be the most sensitive methods for detection of Legionella DNA in water samples. Both PCR modifications showed a high correlation with recovery of Legionella by culture (p<0.01), while no correlation occurred between the results of one-stage PCR and culture (p>0.1).
NASA Astrophysics Data System (ADS)
Mulligan, Jeffrey A.; Adie, Steven G.
2017-02-01
Mechanobiology is an emerging field which seeks to link mechanical forces and properties to the behaviors of cells and tissues in cancer, stem cell growth, and other processes. Traction force microscopy (TFM) is an imaging technique that enables the study of traction forces exerted by cells on their environment to migrate as well as sense and manipulate their surroundings. To date, TFM research has been performed using incoherent imaging modalities and, until recently, has been largely confined to the study of cell-induced tractions within two-dimensions using highly artificial and controlled environments. As the field of mechanobiology advances, and demand grows for research in physiologically relevant 3D culture and in vivo models, TFM will require imaging modalities that support such settings. Optical coherence microscopy (OCM) is an interferometric imaging modality which enables 3D cellular resolution imaging in highly scattering environments. Moreover, optical coherence elastography (OCE) enables the measurement of tissue mechanical properties. OCE relies on the principle of measuring material deformations in response to artificially applied stress. By extension, similar techniques can enable the measurement of cell-induced deformations, imaged with OCM. We propose traction force optical coherence microscopy (TF-OCM) as a natural extension and partner to existing OCM and OCE methods. We report the first use of OCM data and digital image correlation to track temporally varying displacement fields exhibited within a 3D culture setting. These results mark the first steps toward the realization of TF-OCM in 2D and 3D settings, bolstering OCM as a platform for advancing research in mechanobiology.
Minuth, Will W; Denk, Lucia
2016-03-01
To meet specific requirements of developing tissues urgently needed in tissue engineering, biomaterial research and drug toxicity testing, a versatile perfusion culture system was developed. First an individual biomaterial is selected and then mounted in a MINUSHEET(®) tissue carrier. After sterilization the assembly is transferred by fine forceps to a 24 well culture plate for seeding cells or mounting tissue on it. To support spatial (3D) development a carrier can be placed in various types of perfusion culture containers. In the basic version a constant flow of culture medium provides contained tissue with always fresh nutrition and respiratory gas. For example, epithelia can be transferred to a gradient container, where they are exposed to different fluids at the luminal and basal side. To observe development of tissue under the microscope, in a different type of container a transparent lid and base are integrated. Finally, stem/progenitor cells are incubated in a container filled by an artificial interstitium to support spatial development. In the past years the described system was applied in numerous own and external investigations. To present an actual overview of resulting experimental data, the present paper was written.
2008-10-20
embedded intelligence and cultural adaptations to the onslaught of robots in society. This volume constitutes a key contribution to the body of... Robotics , CNRS/Toulouse University, France Nathalie COLINEAU, Language & Multi-modality, CSIRO, Australia Roberto CORDESCHI, Computation & Communication...Intelligence, SONY CSL Paris Nik KASABOV, Computer and Information Sciences, Auckland University, New Zealand Oussama KHATIB, Robotics & Artificial
Drag Enhancement of Microbial Slime Films on Rotating Discs.
1981-03-27
barnacle and algal growth , had also occurred (7). Laboratory culture eliminated these contaminants. The bacteria were grown in artificial seawater (Instant...attachment and growth under flow conditions , using an aquarium power filter pump (12). Films grown in this manner were sufficiently adherent to plastic...the large and easily visible organisms, such as barnacles, bryozoa, and tubeworms do not prevent attachment and growth of micro-organisms, which may
Benjamin O. Knapp; G. Geoff Wang; Joan L. Walker
2013-01-01
Longleaf pine restoration is a common management objective in the southeastern United States and requires artificial regeneration of longleaf pines on sites currently dominated by loblolly pine. In many cases, retention of canopy trees during stand conversion may be desirable to promote ecological function and meet conservation objectives. We tested the effects of...
Li, Hong; Chen, Chen; Ge, Yunsheng; Chen, Shiyi
2014-05-01
To enhance graft ligamentization after anterior cruciate ligament (ACL) reconstruction, human fibronectin (FN) was coated on polyethylene terephthalate (PET) ligaments by spray painting. The FN-coated PET ligaments were investigated in vitro using rat mesenchymal stromal cells (MSCs). MSCs cultured on FN-coated grafts resulted in similar cell densities and amounts of proliferating cells with control grafts without coating. The FN-coated group not only gave rise to MSC-derived collagen-like tissues but also enhanced the expression of collagen-I gene. Furthermore, rat ACL reconstruction models were used to evaluate the effect of the FN coating in vivo. The FN coating significantly promoted new ligament tissue regeneration into the graft fibers. In conclusion, sprayed FN coating had a positive effect to enhance graft ligamentization of PET artificial ligament.
Wang, Hui; Lai, Yue-Kun; Zheng, Ru-Yue; Bian, Ye; Zhang, Ke-Qin; Lin, Chang-Jian
2015-01-01
Biological performance of artificial implant materials is closely related to their surface characteristics, such as microtopography, and composition. Therefore, convenient fabrication of artificial implant materials with a cell-friendly surface structure and suitable composition was of great significance for current tissue engineering. In this work, titanate materials with a nanotubular structure were successfully fabricated through a simple chemical treatment. Immersion test in a simulated body fluid and in vitro cell culture were used to evaluate the biological performance of the treated samples. The results demonstrate that the titanate layer with a nanotubular structure on Ti substrates can promote the apatite-inducing ability remarkably and greatly enhance cellular responses. This highlights the potential of such titanate biomaterials with the special nanoscale structure and effective surface composition for biomedical applications such as bone implants. PMID:26089665
Looking into the Future: Toward Advanced 3D Biomaterials for Stem-Cell-Based Regenerative Medicine.
Liu, Zhongmin; Tang, Mingliang; Zhao, Jinping; Chai, Renjie; Kang, Jiuhong
2018-04-01
Stem-cell-based therapies have the potential to provide novel solutions for the treatment of a variety of diseases, but the main obstacles to such therapies lie in the uncontrolled differentiation and functional engraftment of implanted tissues. The physicochemical microenvironment controls the self-renewal and differentiation of stem cells, and the key step in mimicking the stem cell microenvironment is to construct a more physiologically relevant 3D culture system. Material-based 3D assemblies of stem cells facilitate the cellular interactions that promote morphogenesis and tissue organization in a similar manner to that which occurs during embryogenesis. Both natural and artificial materials can be used to create 3D scaffolds, and synthetic organic and inorganic porous materials are the two main kinds of artificial materials. Nanotechnology provides new opportunities to design novel advanced materials with special physicochemical properties for 3D stem cell culture and transplantation. Herein, the advances and advantages of 3D scaffold materials, especially with respect to stem-cell-based therapies, are first outlined. Second, the stem cell biology in 3D scaffold materials is reviewed. Third, the progress and basic principles of developing 3D scaffold materials for clinical applications in tissue engineering and regenerative medicine are reviewed. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
In vitro biocompatibility of EPM and EPDM rubbers.
Mast, F; Hoschtitzky, J A; Van Blitterswijk, C A; Huysmans, H A
1997-01-01
The in vitro toxicity of two EPDM rubbers (K 778 and K 4802) and one EPM rubber (K 740) was tested using human fibroblasts. The modulus of elasticity of each rubber was varied by exposure to different amounts of electron-beam radiation (0, 5 and 10 Mrad). The short-term in vitro toxicity was tested by culturing cells on polymer films. The long-term effect of ageing was simulated by growing fibroblasts in nutrient media prepared from extracts of heat-exposed materials. Cell cultures were studied both quantitatively and (ultra) structurally. Growth curves obtained in the toxicity test did not differ significantly from control values at any day of observation, and also showed that electron-beam radiation did not alter the biocompatibility. The same results were found for all but one material in the artificial ageing test. The number of cells in the K4802/10 Mrad extraction medium was decreased. Ultrastructurally no gross deviations from normal morphology were observed, either in the direct contact test or in the artificial ageing test. The most characteristic feature was a somewhat dilated endoplasmic reticulum. In summary, the in vitro biocompatibility of EPDM-rubbers as observed in this study is satisfactory and motivates further investigation of their biocompatibility in animal experiments.
Sambi, Manpreet; Chow, Theresa; Whiteley, Jennifer; Li, Mira; Chua, Shawn; Raileanu, Vanessa; Rogers, Ian M
2017-08-01
The development of strategies for tissue regeneration and bio-artificial organ development is based on our understanding of embryogenesis. Differentiation protocols attempt to recapitulate the signaling modalities of gastrulation and organogenesis, coupled with cell selection regimens to isolate the cells of choice. This strategy is impeded by the lack of optimal in vitro culture systems since traditional culture systems do not allow for the three-dimensional interaction between cells and the extracellular matrix. While artificial three-dimensional scaffolds are available, using the natural extracellular matrix scaffold is advantageous because it has a distinct architecture that is difficult to replicate. The adult extracellular matrix is predicted to mediate signaling related to tissue repair not embryogenesis but existing similarities between the two argues that the extracellular matrix will influence the differentiation of stem and progenitor cells. Previous studies using undifferentiated embryonic stem cells grown directly on acellular kidney ECM demonstrated that the acellular kidney supported cell growth but limited differentiation occurred. Using mouse kidney extracellular matrix and mouse embryonic stem cells we report that the extracellular matrix can support the development of kidney structures if the stem cells are first differentiated to kidney progenitor cells before being applied to the acellular organ.
Erikson, Henrik; Salzmann-Erikson, Martin
It is highly likely that artificial intelligence (AI) will be implemented in nursing robotics in various forms, both in medical and surgical robotic instruments, but also as different types of droids and humanoids, physical reinforcements, and also animal/pet robots. Exploring and discussing AI and robotics in nursing and health care before these tools become commonplace is of great importance. We propose that monsters in popular culture might be studied with the hope of learning about situations and relationships that generate empathic capacities in their monstrous existences. The aim of the article is to introduce the theoretical framework and assumptions behind this idea. Both robots and monsters are posthuman creations. The knowledge we present here gives ideas about how nursing science can address the postmodern, technologic, and global world to come. Monsters therefore serve as an entrance to explore technologic innovations such as AI. Analyzing when and why monsters step out of character can provide important insights into the conceptualization of caring and nursing as a science, which is important for discussing these empathic protocols, as well as more general insight into human knowledge. The relationship between caring, monsters, robotics, and AI is not as farfetched as it might seem at first glance.
Erikson, Henrik; Salzmann-Erikson, Martin
2016-01-01
It is highly likely that artificial intelligence (AI) will be implemented in nursing robotics in various forms, both in medical and surgical robotic instruments, but also as different types of droids and humanoids, physical reinforcements, and also animal/pet robots. Exploring and discussing AI and robotics in nursing and health care before these tools become commonplace is of great importance. We propose that monsters in popular culture might be studied with the hope of learning about situations and relationships that generate empathic capacities in their monstrous existences. The aim of the article is to introduce the theoretical framework and assumptions behind this idea. Both robots and monsters are posthuman creations. The knowledge we present here gives ideas about how nursing science can address the postmodern, technologic, and global world to come. Monsters therefore serve as an entrance to explore technologic innovations such as AI. Analyzing when and why monsters step out of character can provide important insights into the conceptualization of caring and nursing as a science, which is important for discussing these empathic protocols, as well as more general insight into human knowledge. The relationship between caring, monsters, robotics, and AI is not as farfetched as it might seem at first glance. PMID:27455058
Evaluation of a modified Cefsulodin-Irgasan-Novobiocin agar for isolation of Yersinia spp.
Tan, Lai Kuan; Ooi, Peck Toung; Carniel, Elisabeth; Thong, Kwai Lin
2014-01-01
Y. enterocolitica and Y. pseudotuberculosis are important food borne pathogens. However, the presence of competitive microbiota makes the isolation of Y. enterocolitica and Y. pseudotuberculosis from naturally contaminated foods difficult. We attempted to evaluate the performance of a modified Cefsulodin-Irgasan-Novobiocin (CIN) agar in the differentiation of Y. enterocolitica from non-Yersinia species, particularly the natural intestinal microbiota. The modified CIN enabled the growth of Y. enterocolitica colonies with the same efficiency as CIN and Luria-Bertani agar. The detection limits of the modified CIN for Y. enterocolitica in culture medium (10 cfu/ml) and in artificially contaminated pork (10(4) cfu/ml) were also comparable to those of CIN. However, the modified CIN provided a better discrimination of Yersinia colonies from other bacteria exhibiting Yersinia-like colonies on CIN (H2S-producing Citrobacter freundii, C. braakii, Enterobacter cloacae, Aeromonas hydrophila, Providencia rettgeri, and Morganella morganii). The modified CIN exhibited a higher recovery rate of Y. enterocolitica from artificially prepared bacterial cultures and naturally contaminated samples compared with CIN. Our results thus demonstrated that the use of modified CIN may be a valuable means to increase the recovery rate of food borne Yersinia from natural samples, which are usually contaminated by multiple types of bacteria.
Ota, Y; Morito, A; Fujisawa, K; Nishida, M; Hata, H; Ueno, T; Yurikusa, T; Murata, T
2012-11-01
A moisturising micro-gel spray for prevention of dryness was compared with commercial products and artificial saliva in vitro and in a clinical setting in patients with cancer. Survival of cultured human gingival epithelial cells was evaluated after treatment with each product for 15 min. A dry test was performed for products giving a 50% survival rate, in which cell survival was measured after drying of cells treated with each product. The survival rates of cells treated with the micro-gel spray and artificial saliva were significantly higher than those of control cells. The micro-gel spray was then evaluated for 1 week in patients with symptoms of dry mouth caused by cancer treatment. There was significant improvement of these symptoms at night and on awakening and of subjective symptoms of decreased salivary volume (P < 0.05). Mean visual analogue scale scores also significantly decreased (P < 0.01). These data suggest that evaluation of moisturising products for dryness prevention can be performed in cultured cells, since products that performed well in vitro also showed good efficacy for symptoms of dry mouth. The micro-gel spray was particularly effective for relieving symptoms of dry mouth in patients with cancer. © 2012 Blackwell Publishing Ltd.
A strategy for rapid production and screening of yeast artificial chromosome libraries.
Strauss, W M; Jaenisch, E; Jaenisch, R
1992-01-01
We describe methods for rapid production and screening of yeast artificial chromosome (YAC) libraries. Utilizing complete restriction digests of mouse genomic DNA for ligations in agarose, a 32,000-clone library was produced and screened in seven weeks. Screening was accomplished by subdividing primary transformation plates into pools of approximately 100 clones which were transferred into a master glycerol stock. These master stocks were used to inoculate liquid cultures to produce culture "pools," and ten pools of 100 clones were then combined to yield superpools of 1,000 clones. Both pool and superpool DNA was screened by polymerase chain reaction (PCR) and positive pools representing 100 clones were then plated on selective medium and screened by in situ hybridization. Screening by the two tiered PCR assay and by in situ hybridization was completed in 4-5 days. Utilizing this methodology we have isolated a 150 kb clone spanning the alpha 1(I) collagen (Col1a1) gene as well as 40 kb clones from the Hox-2 locus. To characterize the representation of the YAC library, the size distribution of genomic Sal I fragments was compared to that of clones picked at random from the library. The results demonstrate significant biasing of the cloned fragment distribution, resulting in a loss of representation for larger fragments.
Valletta, Elisa; Kučera, Lukáš; Prokeš, Lubomír; Amato, Filippo; Pivetta, Tiziana; Hampl, Aleš; Havel, Josef; Vaňhara, Petr
2016-01-01
Cross-contamination of eukaryotic cell lines used in biomedical research represents a highly relevant problem. Analysis of repetitive DNA sequences, such as Short Tandem Repeats (STR), or Simple Sequence Repeats (SSR), is a widely accepted, simple, and commercially available technique to authenticate cell lines. However, it provides only qualitative information that depends on the extent of reference databases for interpretation. In this work, we developed and validated a rapid and routinely applicable method for evaluation of cell culture cross-contamination levels based on mass spectrometric fingerprints of intact mammalian cells coupled with artificial neural networks (ANNs). We used human embryonic stem cells (hESCs) contaminated by either mouse embryonic stem cells (mESCs) or mouse embryonic fibroblasts (MEFs) as a model. We determined the contamination level using a mass spectra database of known calibration mixtures that served as training input for an ANN. The ANN was then capable of correct quantification of the level of contamination of hESCs by mESCs or MEFs. We demonstrate that MS analysis, when linked to proper mathematical instruments, is a tangible tool for unraveling and quantifying heterogeneity in cell cultures. The analysis is applicable in routine scenarios for cell authentication and/or cell phenotyping in general.
Prokeš, Lubomír; Amato, Filippo; Pivetta, Tiziana; Hampl, Aleš; Havel, Josef; Vaňhara, Petr
2016-01-01
Cross-contamination of eukaryotic cell lines used in biomedical research represents a highly relevant problem. Analysis of repetitive DNA sequences, such as Short Tandem Repeats (STR), or Simple Sequence Repeats (SSR), is a widely accepted, simple, and commercially available technique to authenticate cell lines. However, it provides only qualitative information that depends on the extent of reference databases for interpretation. In this work, we developed and validated a rapid and routinely applicable method for evaluation of cell culture cross-contamination levels based on mass spectrometric fingerprints of intact mammalian cells coupled with artificial neural networks (ANNs). We used human embryonic stem cells (hESCs) contaminated by either mouse embryonic stem cells (mESCs) or mouse embryonic fibroblasts (MEFs) as a model. We determined the contamination level using a mass spectra database of known calibration mixtures that served as training input for an ANN. The ANN was then capable of correct quantification of the level of contamination of hESCs by mESCs or MEFs. We demonstrate that MS analysis, when linked to proper mathematical instruments, is a tangible tool for unraveling and quantifying heterogeneity in cell cultures. The analysis is applicable in routine scenarios for cell authentication and/or cell phenotyping in general. PMID:26821236
Degen, J; Uebele, A; Retze, A; Schmid-Staiger, U; Trösch, W
2001-12-28
A newly developed flat panel airlift photobioreactor with a defined circulation path was tested for microalgal culture. The bioreactor exposed the cells to intermittent light to improve the efficiency of light utilization through the flashing-light effect. During batch cultures in the new photobioreactor, the biomass productivity of Chlorella vulgaris was 1.7 times greater than in a randomly mixed bubble column of identical dimension. A reduction in light path from 30 to 15 mm increased the biomass productivity by 2.5-fold. A maximum dry biomass productivity of 0.11 g l(-1) h(-1) was obtained at an artificial illumination of 980 mu E m(-2) s(-1).
An evaluation of trout culture
1940-01-01
In an evaluation of the efficiency of trout culture, the author presents a detailed analysis of complete loss records from 288 individual lots of trout at twenty-two hatcheries in the western United States. Summarized data are given to show the percentage loss of eggs, fry, and fingerlings by progressive one-half inch size groups. The accumulative percentage loss is also included to indicate the losses, under average hatchery conditions, between the egg stage and each successive size-group. These data cover the individual species of trout commonly reared in hatcheries; summarized data are given also for all species combined. A brief discussion of hatchery losses, natural losses, and the cost of artificial propagation is included.
Sikiric, P; Separovic, J; Buljat, G; Anic, T; Stancic-Rokotov, D; Mikus, D; Marovic, A; Prkacin, I; Duplancic, B; Zoricic, I; Aralica, G; Lovric-Bencic, M; Ziger, T; Perovic, D; Rotkvic, I; Mise, S; Hanzevacki, M; Hahn, V; Seiwerth, S; Turkovic, B; Grabarevic, Z; Petek, M; Rucman, R
2000-01-01
Various antidepressants have antiulcer activity. Likewise, the models currently used in ulcers and depression disorders research have a considerable degree of similarity. Therefore, the possibility that depression disorders could be effectively influenced by a primary antiulcer agent with a cyto/organoprotective activity, such as the novel stomach pentadecapeptide BPC 157, was investigated in two rat depression assays. First, a forced swimming test (a Porsolt's procedure) was used. As a more severe procedure, chronic unpredictable stress (after 5 d of unpredictable stress protocol, once daily drug application during stress procedure, open field-immobility test assessment at fourth or sixth day of medication) was used. In a forced swimming test, a reduction of the immobility time in BPC 157 (10 microg, 10 ng x kg(-1) i.p.) treated rats corresponds to the activity of the 15 mg or 40 mg (i.p.) of conventional antidepressants, imipramine or nialamide, respectively, given according to the original Porsolt's protocol. In chronic unpredictable stress procedure, particular aggravation of experimental conditions markedly affected the conventional antidepressant activity, whereas BPC 157 effectiveness was continuously present. The effect of daily imipramine (30 mg) medication could be seen only after a more prolonged period, but not after a shorter period (i.e., 4-d protocol). In these conditions, no delay in the effectiveness was noted in BPC 157 medication and a reduction of the immobility of chronically stressed rats was noted after both 4 and 6 d of BPC 157 (10 microg, 10 ng) medication.
Nelson, Brady D; Bishop, Jeffrey R; Sarapas, Casey; Kittles, Rick A; Shankman, Stewart A
2014-06-01
Research has indicated that individuals of Asian descent, relative to other racial groups, demonstrate reduced emotional responding and lower prevalence rates of several anxiety disorders. It is unclear though whether these group differences extend to biomarkers of anxiety disorders and whether genetic differences play a role. This study compared self-identified Caucasian, Latino, and Asian persons (total N = 174) on startle response during a baseline period and while anticipating unpredictable threat-a putative biomarker for certain anxiety disorders--as well as predictable threat. In addition, the association between genetic ancestry and startle response was examined within each racial group to determine potential genetic influences on responding. For the baseline period, Asian participants exhibited a smaller startle response relative to Caucasian and Latino participants, who did not differ. Within each racial group, genetic ancestry was associated with baseline startle. Furthermore, genetic ancestry mediated racial group differences in baseline startle. For the threat conditions, a Race × Condition interaction indicated that Asian participants exhibited reduced startle potentiation to unpredictable, but not predicable, threat relative to Caucasian and Latino participants, who did not differ. However, genetic ancestry was not associated with threat-potentiated startle in any racial group. This study adds to the growing literature on racial differences in emotional responding and provides preliminary evidence suggesting that genetic ancestry may play an important role. Moreover, reduced sensitivity to unpredictable threat may reflect a mechanism for why individuals of Asian descent are at less risk for particular anxiety disorders relative to other racial groups.
Araujo, Stífani Machado; Poetini, Marcia Rósula; Bortolotto, Vandreza Cardoso; de Freitas Couto, Shanda; Pinheiro, Franciane Cabral; Meichtry, Luana Barreto; de Almeida, Francielli Polet; Santos Musachio, Elize Aparecida; de Paula, Mariane Trindade; Prigol, Marina
2018-05-24
The etiopathogenesis of depression may involve repeated exposure to several unpredictable stressors. This study was conducted to investigate changes induced by chronic unpredictable mild stress (CUMS) and to assess behavioral and neurochemical changes that predict depressive-like behavior in Drosophila melanogaster. Male Drosophila melanogaster flies were exposed to CUMS with several stressors (cold, heat, starvation, and sleep deprivation) in an unpredictable and chronic manner for ten days. At the end of treatment, in vivo behavioral tests (open field, aggression, forced swimming, mating, light/dark box, male fertility evaluation, sucrose preference, weight evaluation) and ex vivo analyses (dopamine and serotonin levels) were performed. Using this CUMS model, we obtained results that contribute to the construction of a depressive model in Drosophila, where we reproduce some behavioral phenotypes corresponding to depressive symptoms, such as immobility in the forced swimming test, less exploration in the light/dark test, changes in mating behavior, changes in the aggressiveness test, reduced sucrose preference, and weight-loss, in addition to a significant reduction in the levels of serotonin and dopamine when compared to the control group. Fluoxetine was used in our study as a positive control to demonstrate that CUMS-induced depressive-like behaviors in flies can be reversed by antidepressants. In conclusion, male Drosophila melanogaster exposed to CUMS display a depressive-like phenotype, and, while this poses some limitations as an animal model for depression, it meets some of the criteria required to be a valid model, such as good face and construct validity. Copyright © 2018. Published by Elsevier B.V.
Ohyama, Junji; Watanabe, Katsumi
2016-01-01
We examined how the temporal and spatial predictability of a task-irrelevant visual event affects the detection and memory of a visual item embedded in a continuously changing sequence. Participants observed 11 sequentially presented letters, during which a task-irrelevant visual event was either present or absent. Predictabilities of spatial location and temporal position of the event were controlled in 2 × 2 conditions. In the spatially predictable conditions, the event occurred at the same location within the stimulus sequence or at another location, while, in the spatially unpredictable conditions, it occurred at random locations. In the temporally predictable conditions, the event timing was fixed relative to the order of the letters, while in the temporally unpredictable condition; it could not be predicted from the letter order. Participants performed a working memory task and a target detection reaction time (RT) task. Memory accuracy was higher for a letter simultaneously presented at the same location as the event in the temporally unpredictable conditions, irrespective of the spatial predictability of the event. On the other hand, the detection RTs were only faster for a letter simultaneously presented at the same location as the event when the event was both temporally and spatially predictable. Thus, to facilitate ongoing detection processes, an event must be predictable both in space and time, while memory processes are enhanced by temporally unpredictable (i.e., surprising) events. Evidently, temporal predictability has differential effects on detection and memory of a visual item embedded in a sequence of images. PMID:26869966
Ohyama, Junji; Watanabe, Katsumi
2016-01-01
We examined how the temporal and spatial predictability of a task-irrelevant visual event affects the detection and memory of a visual item embedded in a continuously changing sequence. Participants observed 11 sequentially presented letters, during which a task-irrelevant visual event was either present or absent. Predictabilities of spatial location and temporal position of the event were controlled in 2 × 2 conditions. In the spatially predictable conditions, the event occurred at the same location within the stimulus sequence or at another location, while, in the spatially unpredictable conditions, it occurred at random locations. In the temporally predictable conditions, the event timing was fixed relative to the order of the letters, while in the temporally unpredictable condition; it could not be predicted from the letter order. Participants performed a working memory task and a target detection reaction time (RT) task. Memory accuracy was higher for a letter simultaneously presented at the same location as the event in the temporally unpredictable conditions, irrespective of the spatial predictability of the event. On the other hand, the detection RTs were only faster for a letter simultaneously presented at the same location as the event when the event was both temporally and spatially predictable. Thus, to facilitate ongoing detection processes, an event must be predictable both in space and time, while memory processes are enhanced by temporally unpredictable (i.e., surprising) events. Evidently, temporal predictability has differential effects on detection and memory of a visual item embedded in a sequence of images.
Nelson, Brady D.; Bishop, Jeffrey R.; Sarapas, Casey; Kittles, Rick A.; Shankman, Stewart A.
2014-01-01
Research has indicated that individuals of Asian descent, relative to other racial groups, demonstrate reduced emotional responding and lower prevalence rates of several anxiety disorders. It is unclear though whether these group differences extend to biomarkers of anxiety disorders and whether genetic differences play a role. The present study compared self-identified Caucasians, Latinos, and Asians (total N = 174) on startle response during a baseline period and while anticipating unpredictable threat–a putative biomarker for certain anxiety disorders–as well as predictable threat. In addition, the association between genetic ancestry and startle response was examined within each racial group to determine potential genetic influences on responding. For the baseline period, Asian participants exhibited a smaller startle response relative to Caucasian and Latino participants, who did not differ. Within each racial group, genetic ancestry was associated with baseline startle. Furthermore, genetic ancestry mediated racial group differences in baseline startle. For the threat conditions, a Race × Condition interaction indicated that Asian participants exhibited reduced startle potentiation to unpredictable, but not predicable, threat relative to Caucasian and Latino participants, who did not differ. However, genetic ancestry was not associated with threat-potentiated startle in any racial group. The present study adds to the growing literature on racial differences in emotional responding and provides preliminary evidence suggesting that genetic ancestry may play an important role. Moreover, reduced sensitivity to unpredictable threat may reflect a mechanism for why individuals of Asian descent are at less risk for particular anxiety disorders relative to other racial groups. PMID:24708496
Artificial milk-feeding women׳s views of their feeding choice in Ireland.
Carroll, Margaret; Gallagher, Louise; Clarke, Mike; Millar, Sally; Begley, Cecily
2015-06-01
despite the well-documented benefits of breast feeding to both mother and child, breast-feeding initiation rates in Ireland are the second lowest in Europe. This study set out to explore the views of women from low socio-economic groups in Ireland on their choice to feed their infants artificial milk, and to elicit factors that may encourage these women to breast feed in the future. a qualitative descriptive approach was used. data were collected through recorded focus groups and individual interviews, using a semi-structured interview schedule. Data were transcribed verbatim. interviews took place in two regions in the Republic of Ireland, north and south. a purposive sample was drawn from the population of 2572 women taking part in the Irish Infant Feeding Study who had never breast fed previously, had intended to, and had, fed this infant artificial milk and who had completed their education before they were 18 years of age. Two focus groups with two women in each were conducted and six women took part in individual interviews. constant comparative analysis was performed to construct the categories and concepts that led to the final themes. these artificial milk-feeding women based their infant feeding decision on many social and experiential factors. The major influences on their decisions were: personal attitudes toward feeding methods, and external influences on infant feeding methods. Attitudes towards other women and feeding future infants reinforced a strong preference towards artificial milk feeding. it is apparent that a prevailing culture that is unreceptive to breast feeding and the lack of positive breast-feeding role models, contributed to a strong commitment to artificial milk feeding for these participants. Promotion of breast feeding must take account of the complex contexts in which women make decisions. Advice regarding breast feeding should take account of women׳s feelings and avoid undue pressure, while still promoting the benefits of breast feeding to women and their families. Copyright © 2015 Elsevier Ltd. All rights reserved.
Rascalou, Adeline; Lamartine, Jérôme; Poydenot, Pauline; Demarne, Frédéric; Bechetoille, Nicolas
2018-05-05
Artificial visible light is everywhere in modern life. Social communication confronts us with screens of all kinds, and their use is on the rise. We are therefore increasingly exposed to artificial visible light, the effects of which on skin are poorly known. The purpose of this study was to model the artificial visible light emitted by electronic devices and assess its effect on normal human fibroblasts. The spectral irradiance emitted by electronic devices was optically measured and equipment was developed to accurately reproduce such artificial visible light. Effects on normal human fibroblasts were analyzed on human genome microarray-based gene expression analysis. At cellular level, visualization and image analysis were performed on the mitochondrial network and F-actin cytoskeleton. Cell proliferation, ATP release and type I procollagen secretion were also measured. We developed a device consisting of 36 LEDs simultaneously emitting blue, green and red light at distinct wavelengths (450 nm, 525 nm and 625 nm) with narrow spectra and equivalent radiant power for the three colors. A dose of 99 J/cm 2 artificial visible light was selected so as not to induce cell mortality following exposure. Microarray analysis revealed 2984 light-modulated transcripts. Functional annotation of light-responsive genes revealed several enriched functions including, amongst others, the "mitochondria" and "integrin signaling" categories. Selected results were confirmed by real-time quantitative PCR, analyzing 24 genes representing these two categories. Analysis of micro-patterned culture plates showed marked fragmentation of the mitochondrial network and disorganization of the F-actin cytoskeleton following exposure. Functionally, there was considerable impairment of cell growth and spread, ATP release and type I procollagen secretion in exposed fibroblasts. Artificial visible light induces drastic molecular and cellular changes in normal human fibroblasts. This may impede normal cellular functions and contribute to premature skin aging. The present results extend our knowledge of the effects of the low-energy wavelengths that are increasingly used to treat skin disorders. Copyright © 2018 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.
The Processing of Attended and Predicted Sounds in Time.
Paris, Tim; Kim, Jeesun; Davis, Chris
2016-01-01
Neural responses to an attended event are typically enhanced relative to those from an unattended one (attention enhancement). Conversely, neural responses to a predicted event are typically reduced relative to those from an unpredicted one (prediction suppression). What remains to be established is what happens with attended and predicted events. To examine the interaction between attention and prediction, we combined two robust paradigms developed for studying attention and prediction effects on ERPs into an orthogonal design. Participants were presented with sounds in attended or unattended intervals with onsets that were either predicted by a moving visual cue or unpredicted (no cue was provided). We demonstrated an N1 enhancement effect for attended sounds and an N1 suppression effect for predicted sounds; furthermore, an interaction between these effects was found that emerged early in the N1 (50-95 msec), indicating that attention enhancement only occurred when the sound was unpredicted. This pattern of results can be explained by the precision of the predictive cue that reduces the need for attention selection in the attended and predicted condition.
Soriano-Melgar, Lluvia de Abril Alexandra; Alcaraz-Meléndez, Lilia; Méndez-Rodríguez, Lía C; Puente, María Esther; Rivera-Cabrera, Fernando; Zenteno-Savín, Tania
2014-05-01
Ultraviolet type B (UV-B) radiation effects on medicinal plants have been recently investigated in the context of climate change, but the modifications generated by UV-B radiation might be used to increase the content of antioxidants, including phenolic compounds. To generate information on the effect of exposure to artificial UV-B radiation at different highdoses in the antioxidant content of damiana plants in an in vitro model. Damiana plantlets (tissue cultures in Murashige- Skoog medium) were irradiated with artificial UV-B at 3 different doses (1) 0.5 ± 0.1 mW cm-2 (high) for 2 h daily, (2) 1 ± 0,1 mW cm-2 (severe) for 2 h daily, or (3) 1 ± 0.1 mW cm-2 for 4 h daily during 3 weeks. The concentration of photosynthetic pigments (chlorophylls a and b, carotenoids), vitamins (C and E) and total phenolic compounds, the enzymatic activity of superoxide dismutase (SOD, EC 1.15.1.1) and total peroxidases (POX, EC 1.11.1), as well as total antioxidant capacity and lipid peroxidation levels were quantified to assess the effect of high artificial UV-B radiation in the antioxidant content of in vitro damiana plants. Severe and high doses of artificial UV-B radiation modified the antioxidant content by increasing the content of vitamin C and decreased the phenolic compound content, as well as modified the oxidative damage of damiana plants in an in vitro model. UV-B radiation modified the antioxidant content in damiana plants in an in vitro model, depending on the intensity and duration of the exposure. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.
Essone, Jean Claude Biteghe Bi; N'Dilimabaka, Nadine; Ondzaga, Julien; Lekana-Douki, Jean Bernard; Mba, Dieudonné Nkoghe; Deloron, Philippe; Mazier, Dominique; Gay, Frédrérick; Touré Ndouo, Fousseyni S
2017-06-27
Plasmodium falciparum infection can progress unpredictably to severe forms including respiratory distress and cerebral malaria. The mechanisms underlying the variable natural course of malaria remain elusive. The cerebral microvascular endothelial cells-D3 and lung endothelial cells both from human were cultured separately and challenged with P. falciparum field isolates taken directly from malaria patients or 3D7 strain (in vitro maintained culture). The capacity of these P. falciparum isolates to induce endothelial cell apoptosis via cytoadherence or not was then assessed. Overall, 27 P. falciparum isolates were collected from patients with uncomplicated malaria (n = 25) or severe malaria (n = 2). About half the isolates (n = 17) were able to bind brain endothelial cells (12 isolates, 44%) or lung endothelial cells (17 isolates, 63%) or both (12 isolates, 44%). Sixteen (59%) of the 27 isolates were apoptogenic for brain and/or lung endothelial cells. The apoptosis stimulus could be cytoadherence, direct cell-cell contact without cytoadherence, or diffusible soluble factors. While some of the apoptogenic isolates used two stimuli (direct contact with or without cytoadherence, plus soluble factors) to induce apoptosis, others used only one. Among the 16 apoptogenic isolates, eight specifically targeted brain endothelial cells, one lung endothelial cells, and seven both. These results indicate that the brain microvascular cell line was more susceptible to apoptosis triggered by P. falciparum than the primary pulmonary endothelial cells and may have relevance to host-parasite interaction.
Presence of mycobacterial L-forms in human blood: Challenge of BCG vaccination
Markova, Nadya; Slavchev, Georgi; Michailova, Lilia
2015-01-01
Possible persistence of bacteria in human blood as cell wall deficient forms (L-forms) represents a top research priority for microbiologists. Application of live BCG vaccine and L-form transformation of vaccine strain may display a new intriguing aspect concerning the opportunity for occurrence of unpredictable colonization inside the human body by unusual microbial life forms. L-form cultures were isolated from 141 blood samples of people previously vaccinated with BCG, none with a history of exposure to tuberculosis. Innovative methodology to access the unusual L-form elements derived from human blood was developed. The methodology outlines the path of transformation of non- cultivable L-form element to cultivable bacteria and their adaptation for growth in vitro. All isolates showed typical L-forms growth features (“fried eggs” colonies and biofilm). Electron microscopy revealed morphology evidencing peculiar characteristics of bacterial L-form population (cell wall deficient polymorphic elements of variable shape and size). Regular detection of acid fast bacteria in smears of isolated blood L-form cultures, led us to start their identification by using specific Mycobactrium spp. genetic tests. Forty five of 97 genetically tested blood cultures provided specific positive signals for mycobacteria, confirmed by at least one of the 3 specific assays (16S rRNA PCR; IS6110 Real Time PCR and spoligotyping). In conclusion, the obtained genetic evidence suggests that these L-forms are of mycobacterial origin. As the investigated people had been vaccinated with BCG, we can assume that the identified mycobacterial L-forms may be produced by persisting live BCG vaccine. PMID:25874947
Induction of ICAM-1 Expression in Mouse Embryonic Fibroblasts Cultured on Fibroin-Gelatin Scaffolds
Nosenko, M. A.; Maluchenko, N. V.; Drutskaya, M. S.; Arkhipova, A. Y.; Agapov, I. I.; Nedospasov, S. A.; Moisenovich, M. M.
2017-01-01
Culturing of allogeneic or autologous cells in three-dimensional bioresorbable scaffolds is an important step in the engineering of constructs for regenerative medicine, as well as for experimental systems to study the mechanisms of cell differentiation and cell-to-cell interaction. Artificial substrates can modulate the phenotype and functional activity of immobilized cells. Investigating these changes is important for understanding the fundamental processes underlying cellular interactions in a 3D microenvironment and for improving tissue-engineered structures. In this study, we investigated the expression of the ICAM-1 adhesion molecule in mouse embryonic fibroblasts (MEF) when cultured on gelatin-fibroin scaffolds. Increased expression of ICAM-1 in MEF was detected only under 3D culture conditions both at the mRNA and protein levels. At the same time, the MEF cultured on various substrates did not oerexpress MAdCAM-1, indicating the selective effect of 3D culture conditions on ICAM-1 expression. One possible mechanism for ICAM-1 induction in MEF is associated with the activation of AP-1, since expression of c-Fos and Junb (but not cJun and Jund) was increased in MEF in 3D. When cultured under 2D conditions, the expression level of AP-1 components did not change. PMID:29104780
Culture of C3A cells in alginate beads for fluidized bed bioartificial liver.
Kinasiewicz, A; Gautier, A; Lewinska, D; Bukowski, J; Legallais, C; Weryński, A
2007-11-01
Extracorporeal bioartificial liver has been designed to sustain the detoxification and synthetic function of the failed liver in patients suffering from acute liver failure until the time of liver allotransplantation or regeneration of their own. A fluidized bed, bioartificial liver improves the mass transfer velocity between the medium and the hepatocytes. Detoxification functions of the liver could be replaced by completely artificial systems, but the synthetic functions of hepatocytes may be obtained only by metabolically active cells. The aim of our study was to investigate the influence of C3A cell culture in alginate beads on synthetic function in a fluidized bed, bioartificial liver. Cells in alginate beads were prepared using an electrostatic droplet generator of our own design using low-viscosity alginate. Beads were cultured for 24 hours then 7 days in static conditions and then 24 hours of fluidization in the bioreactor to assess albumin production. We observed significantly increased albumin production by C3A cells entrapped in alginate beads during static culture. Fluidization increased albumin production compared with static culture. Fluidization performed after 7 days of static culture resulted in a significant increase in albumin synthesis. In conclusion, static culture of alginate beads hosting hepatic cells facilitates restoration of cell function.
3D Cell Culture in Alginate Hydrogels
Andersen, Therese; Auk-Emblem, Pia; Dornish, Michael
2015-01-01
This review compiles information regarding the use of alginate, and in particular alginate hydrogels, in culturing cells in 3D. Knowledge of alginate chemical structure and functionality are shown to be important parameters in design of alginate-based matrices for cell culture. Gel elasticity as well as hydrogel stability can be impacted by the type of alginate used, its concentration, the choice of gelation technique (ionic or covalent), and divalent cation chosen as the gel inducing ion. The use of peptide-coupled alginate can control cell–matrix interactions. Gelation of alginate with concomitant immobilization of cells can take various forms. Droplets or beads have been utilized since the 1980s for immobilizing cells. Newer matrices such as macroporous scaffolds are now entering the 3D cell culture product market. Finally, delayed gelling, injectable, alginate systems show utility in the translation of in vitro cell culture to in vivo tissue engineering applications. Alginate has a history and a future in 3D cell culture. Historically, cells were encapsulated in alginate droplets cross-linked with calcium for the development of artificial organs. Now, several commercial products based on alginate are being used as 3D cell culture systems that also demonstrate the possibility of replacing or regenerating tissue. PMID:27600217
Raman, Shanti; Nicholls, Rachel; Ritchie, Jan; Razee, Husna; Shafiee, Samaneh
2016-07-28
The perinatal period, i.e. pregnancy, childbirth and early infancy, is a significant transition period where the biological and the social strongly intersect. In low and middle-income countries the disease burden arising from the perinatal period, is still substantial. The perinatal period is also a crucial window of opportunity for reducing undernutrition and its long term adverse effects. We explored qualitative research conducted in low resource settings around the perinatal continuum over the past two decades, with a particular focus on the 'cultural' realm, to identify common themes influencing maternal and infant nutrition. We systematically searched electronic databases from 1990 to 2014, including MEDLINE, EMBASE, PsycINFO, Scopus and Cumulative Index to Nursing and Allied Health Literature, using relevant search terms including traditional beliefs, practices, pregnancy, childbirth, developing countries etc. Adapted Consolidated Criteria for Reporting Qualitative Health Research and Critical Appraisal Skills Programme criteria were used to determine quality of studies. We synthesised the literature thematically, enabled by NVivo 10 software. Most studies showed cultural support for breastfeeding, although most traditional societies delayed breastfeeding due to colostrum being considered 'dirty'. A range of restrictive practices through pregnancy and the post- partum period were revealed in Asia, Latin America and Africa. There was a strong cultural understanding of the healing power of everyday foods. A wide range of good foods and bad foods continued to have currency through the perinatal continuum, with little consensus between groups of what was beneficial versus harmful. Cross-cutting themes that emerged were 1) the role of the woman/mother/wife as strong and good; 2) poverty restricting women's nutrition choices; 3) change being constant, but the direction of change unpredictable. A rich and diverse repertoire of cultural practices and beliefs influenced perinatal nutrition. Results from this synthesis should influence public health policymakers and practitioners, to tailor contextually specific, culturally responsive perinatal nutrition interventions to optimise health and wellbeing of mother-infant dyads. Ideally these interventions should build on culturally sanctioned life affirming behaviours such as breastfeeding, promoting post-partum rest and recovery, while modifying the potentially harmful aspects of other cultural practices in the perinatal period.
Reconstitution of a Patterned Neural Tube from Single Mouse Embryonic Stem Cells.
Ishihara, Keisuke; Ranga, Adrian; Lutolf, Matthias P; Tanaka, Elly M; Meinhardt, Andrea
2017-01-01
The recapitulation of tissue development and patterning in three-dimensional (3D) culture is an important dimension of stem cell research. Here, we describe a 3D culture protocol in which single mouse ES cells embedded in Matrigel under neural induction conditions clonally form a lumen containing, oval-shaped epithelial structure within 3 days. By Day 7 an apicobasally polarized neuroepithelium with uniformly dorsal cell identity forms. Treatment with retinoic acid at Day 2 results in posteriorization and self-organization of dorsal-ventral neural tube patterning. Neural tube organoid growth is also supported by pure laminin gels as well as poly(ethylene glycol) (PEG)-based artificial extracellular matrix hydrogels, which can be fine-tuned for key microenvironment characteristics. The rapid generation of a simple, patterned tissue in well-defined culture conditions makes the neural tube organoid a tractable model for studying neural stem cell self-organization.
Optimization of a Viability PCR Method for the Detection of Listeria monocytogenes in Food Samples.
Agustí, Gemma; Fittipaldi, Mariana; Codony, Francesc
2018-06-01
Rapid detection of Listeria and other microbial pathogens in food is an essential part of quality control and it is critical for ensuring the safety of consumers. Culture-based methods for detecting foodborne pathogens are time-consuming, laborious and cannot detect viable but non-culturable microorganism, whereas viability PCR methodology provides quick results; it is able to detect viable but non-culturable cells, and allows for easier handling of large amount of samples. Although the most critical point to use viability PCR technique is achieving the complete exclusion of dead cell amplification signals, many improvements are being introduced to overcome this. In the present work, the yield of dead cell DNA neutralization was enhanced by incorporating two new sample treatment strategies: tube change combined with a double light treatment. This procedure was successfully tested using artificially contaminated food samples, showing improved neutralization of dead cell DNA.
Chen, Zhanfei; Lian, Fen; Wang, Xiaoqian; Chen, Yanling; Tang, Nanhong
The polyamidoamine (PAMAM) dendrimer, a type of macromolecule material, has been used in spheroidal cell culture and drug delivery in recent years. However, PAMAM is not involved in the study of hepatic cell-spheroid culture or its biological activity, particularly in detoxification function. Here, we constructed a PAMAM-dendrimer conjugate decorated by an integrin ligand: arginine-glycine-aspartic acid (RGD) peptide. Our studies demonstrate that RGD-polyethylene glycol (PEG)-PAMAM conjugates can promote singly floating hepatic cells to aggregate together in a sphere-like growth with a weak reactive oxygen species. Moreover, RGD-PEG-PAMAM conjugates can activate the AKT-MAPK pathway in hepatic cells to promote cell proliferation and improve basic function and ammonia metabolism. Together, our data support the hepatocyte sphere treated by RGD-PEG-PAMAM conjugates as a potential source of hepatic cells for a biological artificial liver system.
Chemical dispersants: Oil biodegradation friend or foe?
Rahsepar, Shokouh; Smit, Martijn P J; Murk, Albertinka J; Rijnaarts, Huub H M; Langenhoff, Alette A M
2016-07-15
Chemical dispersants were used in response to the Deepwater Horizon oil spill in the Gulf of Mexico, both at the sea surface and the wellhead. Their effect on oil biodegradation is unclear, as studies showed both inhibition and enhancement. This study addresses the effect of Corexit on oil biodegradation by alkane and/or aromatic degrading bacterial culture in artificial seawater at different dispersant to oil ratios (DORs). Our results show that dispersant addition did not enhance oil biodegradation. At DOR 1:20, biodegradation was inhibited, especially when only the alkane degrading culture was present. With a combination of cultures, this inhibition was overcome after 10days. This indicates that initial inhibition of oil biodegradation can be overcome when different bacteria are present in the environment. We conclude that the observed inhibition is related to the enhanced dissolution of aromatic compounds into the water, inhibiting the alkane degrading bacteria. Copyright © 2016 Elsevier Ltd. All rights reserved.
Muthusubramanian, Venkateshwaran; Bandyopadhyay, Ranajit; Rajaram Reddy, Daram; Tooley, Paul W
2006-04-01
Sorghum ergot in India is caused by Claviceps africana and C. sorghi. The distributions of these two species in India is not known. Eighty-nine sorghum ergot isolates were cultured from young sphacelia obtained from male sterile sorghum plants artificially inoculated using inoculum collected in the field. Based on cultural characteristics, the isolates were separated into two groups which differed distinctly in the morphology of their sphacelia, conidia, and sclerotia. Marked differences also were observed in rates of secondary conidial production and disease spread between the groups. In combination with molecular evidence, our results confirm that the isolates placed in Group I represent C. africana and Group II isolates represent C. sorghi. C. africana was found to be widely distributed in all sorghum growing areas of India. The species first described as occuring in India, C. sorghi, appears to be restricted to a few locations in the states of Maharashtra, Andhra Pradesh, and Karnataka.
DOE Office of Scientific and Technical Information (OSTI.GOV)
McIlwaine, D.B.; Diemer, J.; Grab, L.
1997-12-01
The efficacy of many commonly used biocides is often determined by laboratory evaluations against a variety of planktonic microorganisms. While these tests provide some information as to the performance of a biocide against a particular microorganism, they may not predict how well the biocide will perform under actual field conditions against the more problematic sissile form of the organisms. In order to address the issue of how well a biocide penetrates and kills the problematic microorganisms contained within a biofilm, an artificial biofilm system utilizing microorganisms embedded in alginate beads has been used to compare the efficacy of biocide treatmentsmore » against both the planktonic and sessile form of the same organism. Pure cultures of Enterobacter aerogenes, as well as mixed field isolates, were used in the experiments. In addition, the alginate beads were prepared with actual system waters taken from a variety of industrial applications. In that way, all of the scale and corrosion inhibitors and other contaminants which are present in the actual system are also present in the model biofilm system. In all cases, the organisms contained within the artificial biofilm were significantly more difficult to kill than the corresponding planktonic microbes.« less
Sakamoto, Kotaro; Kawata, Yayoi; Masuda, Yasushi; Umemoto, Tadashi; Ito, Takashi; Asami, Taiji; Takekawa, Shiro; Ohtaki, Tetsuya; Inooka, Hiroshi
2016-11-04
Fibroblast growth factor receptor-1c (FGFR1c)/βKlotho (KLB) complex is a receptor of fibroblast growth factor 21 (FGF21). Pharmacologically, FGF21 shows anti-obesity and anti-diabetic effects upon peripheral administration. Here, we report the development of an artificial peptide agonist to the FGFR1c/KLB heterodimer complex. The peptide, F91-8A07 (LPGRTCREYPDLWWVRCY), was discovered from random peptide T7 phage display and selectively bound to the FGFR1c/KLB complex, but not to FGFR1c and KLB individually. After subsequent peptide dimerization using a short polyethyleneglycol (PEG) linker, the dimeric F91-8A07 peptide showed higher potent agonist activity than that of FGF21 in cultured primary human adipocytes. Moreover, the dimeric peptide led to an expression of the early growth response protein-1 (Egr-1) mRNA in vivo, which is a target gene of FGFR1c. To the best of our knowledge, this is the first report of a FGFR1c/KLB complex-selective artificial peptide agonist. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
NASA Technical Reports Server (NTRS)
Sword, A. J.; Park, W. T.
1975-01-01
A teleoperator system with a computer for manipulator control to combine the capabilities of both man and computer to accomplish a task is described. This system allows objects in unpredictable locations to be successfully located and acquired. By using a method of characterizing the work-space together with man's ability to plan a strategy and coarsely locate an object, the computer is provided with enough information to complete the tedious part of the task. In addition, the use of voice control is shown to be a useful component of the man/machine interface.
Arab, Mohammad M.; Yadollahi, Abbas; Shojaeiyan, Abdolali; Ahmadi, Hamed
2016-01-01
One of the major obstacles to the micropropagation of Prunus rootstocks has, up until now, been the lack of a suitable tissue culture medium. Therefore, reformulation of culture media or modification of the mineral content might be a breakthrough to improve in vitro multiplication of G × N15 (garnem). We found artificial neural network in combination of genetic algorithm (ANN-GA) as a very precise and powerful modeling system for optimizing the culture medium, So that modeling the effects of MS mineral salts (NH4+, NO3-, PO42-, Ca2+, K+, SO42-, Mg2+, and Cl−) on in vitro multiplication parameters (the number of microshoots per explant, average length of microshoots, weight of calluses derived from the base of stem explants, and quality index of plantlets) of G × N15. Showed high R2 correlation values of 87, 91, 87, and 74 between observed and predicted values were found for these four growth parameters, respectively. According to the ANN-GA results, among the input variables, NH4+ and NO3- had the highest values of VSR in data set for the parameters studied. The ANN-GA showed that the best proliferation rate was obtained from medium containing (mM) 27.5 NO3-, 14 NH4+, 5 Ca2+, 25.9 K+, 0.7 Mg2+, 1.1 PO42-, 4.7 SO42-, and 0.96 Cl−. The performance of the medium optimized by ANN-GA, denoted as YAS (Yadollahi, Arab and Shojaeiyan), was compared to that of standard growth media for all Prunus rootstock, including the Murashige and Skoog (MS) medium, (specific media) EM, Quoirin and Lepoivre (QL) medium, and woody plant medium (WPM) Prunus. With respect to shoot length, shoot number per cultured explant and productivity (number of microshoots × length of microshoots), YAS was found to be superior to other media for in vitro multiplication of G × N15 rootstocks. In addition, our results indicated that by using ANN-GA, we were able to determine a suitable culture medium formulation to achieve the best in vitro productivity. PMID:27807436
Kaziród-Wolski, Karol; Sielski, Janusz; Ciuraszkiewicz, Katarzyna
2017-01-23
Diagnosis and treatment of infective endocarditis (IE) is still a challenge for physicians. Group of patients with the worst prognosis is treated in Intensive Cardiac Care Unit (ICCU). Etiologic agent can not be identified in a substantial number of patients. The aim of study is to find differences between patients with blood culture negative infective endocarditis (BCNIE) and blood culture positive infective endocarditis (BCPIE) treated in ICCU by comparing their clinical course and laboratory parameters. Retrospective analysis of 30 patients with IE hospitalized in ICCU Swietokrzyskie Cardiac Centre between 2010 and 2016. This group consist of 26 men (86,67%) and 4 women (13,3%). Mean age was 58 years ±13. Most of the cases were new disease, recurrence of the disease was observed in 2 cases (6,7%). 8 patients (26,7%) required artificial ventilation, 11 (36,7%) received inotropes and 6 (20%) vasopresors. In 14 (46,7%) cases blood cultures was negative (BCNIE), the rest of patients (16, 53,3%) was blood cultures - positive infective endocarditis (BCIE). Both of the groups were clinically similar. There were no statistically significant differences in incidence of cardiac implants, localization of bacterial vegetations, administered catecholamines, antibiotic therapy, artificial ventilation, surgical treatment, complication and in-hospital mortality. Incidence of cardiac complications in all of BCNIE cases and in 81,3% cases of BCPIE draws attention, but it is not statistically significant difference (p=0,08). There was statistically significant difference in mean BNP blood concentration (3005,17 ng/ml ±2045,2 vs 1013,42 ng/ml ±1087,6; p=0,01), but there were no statistically significant differences in rest of laboratory parameters. BCNIE group has got higher mean BNP blood concentration than BCPIE group. There were no statistically significant differences between these groups in others laboratory parameters, clinical course and administered antibiotic therapy. In our endemic region major cause of BCNIE seems to be early antibiotic therapy prior to collection of blood samples, but further studies are necessary.
Yuan, Suxia; Su, Yanbin; Liu, Yumei; Li, Zhansheng; Fang, Zhiyuan; Yang, Limei; Zhuang, Mu; Zhang, Yangyong; Lv, Honghao; Sun, Peitian
2015-01-01
Chromosome doubling of microspore-derived plants is an important factor in the practical application of microspore culture technology because breeding programs require a large number of genetically stable, homozygous doubled haploid plants with a high level of fertility. In the present paper, 29 populations of microspore-derived plantlets from cabbage (Brassica oleracea var. capitata) and broccoli (Brassica oleracea var. italica) were used to study the ploidy level and spontaneous chromosome doubling of these populations, the artificial chromosome doubling induced by colchicine, and the influence of tissue culture duration on the chromosomal ploidy of the microspore-derived regenerants. Spontaneous chromosome doubling occurred randomly and was genotype dependent. In the plant populations derived from microspores, there were haploids, diploids, and even a low frequency of polyploids and mixed-ploidy plantlets. The total spontaneous doubling in the 14 cabbage populations ranged from 0 to 76.9%, compared with 52.2 to 100% in the 15 broccoli populations. To improve the rate of chromosome doubling, an efficient and reliable artificial chromosome doubling protocol (i.e., the immersion of haploid plantlet roots in a colchicine solution) was developed for cabbage and broccoli microspore-derived haploids. The optimal chromosome doubling of the haploids was obtained with a solution of 0.2% colchicine for 9–12 h or 0.4% colchicine for 3–9 h for cabbage and 0.05% colchicine for 6–12 h for broccoli. This protocol produced chromosome doubling in over 50% of the haploid genotypes for most of the populations derived from cabbage and broccoli. Notably, after 1 or more years in tissue culture, the chromosomes of the haploids were doubled, and most of the haploids turned into doubled haploid or mixed-ploidy plants. This is the first report indicating that tissue culture duration can change the chromosomal ploidy of microspore-derived regenerants. PMID:26734028
Yuan, Suxia; Su, Yanbin; Liu, Yumei; Li, Zhansheng; Fang, Zhiyuan; Yang, Limei; Zhuang, Mu; Zhang, Yangyong; Lv, Honghao; Sun, Peitian
2015-01-01
Chromosome doubling of microspore-derived plants is an important factor in the practical application of microspore culture technology because breeding programs require a large number of genetically stable, homozygous doubled haploid plants with a high level of fertility. In the present paper, 29 populations of microspore-derived plantlets from cabbage (Brassica oleracea var. capitata) and broccoli (Brassica oleracea var. italica) were used to study the ploidy level and spontaneous chromosome doubling of these populations, the artificial chromosome doubling induced by colchicine, and the influence of tissue culture duration on the chromosomal ploidy of the microspore-derived regenerants. Spontaneous chromosome doubling occurred randomly and was genotype dependent. In the plant populations derived from microspores, there were haploids, diploids, and even a low frequency of polyploids and mixed-ploidy plantlets. The total spontaneous doubling in the 14 cabbage populations ranged from 0 to 76.9%, compared with 52.2 to 100% in the 15 broccoli populations. To improve the rate of chromosome doubling, an efficient and reliable artificial chromosome doubling protocol (i.e., the immersion of haploid plantlet roots in a colchicine solution) was developed for cabbage and broccoli microspore-derived haploids. The optimal chromosome doubling of the haploids was obtained with a solution of 0.2% colchicine for 9-12 h or 0.4% colchicine for 3-9 h for cabbage and 0.05% colchicine for 6-12 h for broccoli. This protocol produced chromosome doubling in over 50% of the haploid genotypes for most of the populations derived from cabbage and broccoli. Notably, after 1 or more years in tissue culture, the chromosomes of the haploids were doubled, and most of the haploids turned into doubled haploid or mixed-ploidy plants. This is the first report indicating that tissue culture duration can change the chromosomal ploidy of microspore-derived regenerants.
NASA Astrophysics Data System (ADS)
Burke, Ariane; Kageyama, Masa; Latombe, Guilllaume; Fasel, Marc; Vrac, Mathieu; Ramstein, Gilles; James, Patrick M. A.
2017-05-01
The extent to which climate change has affected the course of human evolution is an enduring question. The ability to maintain spatially extensive social networks and a fluid social structure allows human foragers to ;map onto; the landscape, mitigating the impact of ecological risk and conferring resilience. But what are the limits of resilience and to which environmental variables are foraging populations sensitive? We address this question by testing the impact of a suite of environmental variables, including climate variability, on the distribution of human populations in Western Europe during the Last Glacial Maximum (LGM). Climate variability affects the distribution of plant and animal resources unpredictably, creating an element of risk for foragers for whom mobility comes at a cost. We produce a model of habitat suitability that allows us to generate predictions about the probable distribution of human populations and discuss the implications of these predictions for the structure of human populations and their social and cultural evolution during the LGM.
Genetic and epigenetic instability of stem cells.
Rajamani, Karthyayani; Li, Yuan-Sheng; Hsieh, Dean-Kuo; Lin, Shinn-Zong; Harn, Horng-Jyh; Chiou, Tzyy-Wen
2014-01-01
Recently, research on stem cells has been receiving an increasing amount of attention, both for its advantages and disadvantages. Genetic and epigenetic instabilities among stem cells have been a recurring obstacle to progress in regenerative medicine using stem cells. Various reports have stated that these instabilities can transform stem cells when transferred in vivo and thus have the potential to develop tumors. Previous research has shown that various extrinsic and intrinsic factors can contribute to the stability of stem cells. The extrinsic factors include growth supplements, growth factors, oxygen tension, passage technique, and cryopreservation. Controlling these factors based on previous reports may assist researchers in developing strategies for the production and clinical application of "safe" stem cells. On the other hand, the intrinsic factors can be unpredictable and uncontrollable; therefore, to ensure the successful use of stem cells in regenerative medicine, it is imperative to develop and implement appropriate strategies and technique for culturing stem cells and to confirm the genetic and epigenetic safety of these stem cells before employing them in clinical trials.
"I didn't feel like I was a person anymore": realigning full adult personhood after ostomy surgery.
Ramirez, Michelle; Altschuler, Andrea; McMullen, Carmit; Grant, Marcia; Hornbrook, Mark; Krouse, Robert
2014-06-01
Colorectal cancer (CRC) is the third most common cancer in the United States. For some CRC patients, cancer treatment involves creating a permanent or temporary intestinal ostomy. Having an ostomy often results in complex social and physical concerns-including unpredictable and at times publicly noticeable bowel output. In this article, we discuss findings from 30 in-depth interviews with female CRC survivors with ostomies in the western United States. We highlight how having an ostomy disrupts culturally sanctioned practices of continence that mark the attainment of full-adult personhood. We discuss how survivors reclaim a sense of full personhood after ostomy surgery through a process of realignment that entails both learning how to manage ostomy equipment to conceal bowel activity and reappraising their illness and suffering. We suggest that the anthropological categories of personhood and personhood realignment be incorporated into research and interventions aimed at increasing support among cancer survivors living with bodily impairments. © 2014 by the American Anthropological Association.
“I Didn’t Feel Like I Was a Person Anymore”: Realigning Full Adult Personhood after Ostomy Surgery
Ramirez, Michelle; Altschuler, Andrea; McMullen, Carmit; Grant, Marcia; Hornbrook, Mark; Krouse, Robert
2016-01-01
Colorectal cancer (CRC) is the third most common cancer in the United States. For some CRC patients, cancer treatment involves creating a permanent or temporary intestinal ostomy. Having an ostomy often results in complex social and physical concerns—including unpredictable and at times publicly noticeable bowel output. In this article, we discuss findings from 30 in-depth interviews with female CRC survivors with ostomies in the western United States. We highlight how having an ostomy disrupts culturally sanctioned practices of continence that mark the attainment of full-adult personhood. We discuss how survivors reclaim a sense of full personhood after ostomy surgery through a process of realignment that entails both learning how to manage ostomy equipment to conceal bowel activity and reappraising their illness and suffering. We suggest that the anthropological categories of personhood and personhood realignment be incorporated into research and interventions aimed at increasing support among cancer survivors living with bodily impairments. PMID:24782269
Cultural transmission results in convergence towards colour term universals
Xu, Jing; Dowman, Mike; Griffiths, Thomas L.
2013-01-01
As in biological evolution, multiple forces are involved in cultural evolution. One force is analogous to selection, and acts on differences in the fitness of aspects of culture by influencing who people choose to learn from. Another force is analogous to mutation, and influences how culture changes over time owing to errors in learning and the effects of cognitive biases. Which of these forces need to be appealed to in explaining any particular aspect of human cultures is an open question. We present a study that explores this question empirically, examining the role that the cognitive biases that influence cultural transmission might play in universals of colour naming. In a large-scale laboratory experiment, participants were shown labelled examples from novel artificial systems of colour terms and were asked to classify other colours on the basis of those examples. The responses of each participant were used to generate the examples seen by subsequent participants. By simulating cultural transmission in the laboratory, we were able to isolate a single evolutionary force—the effects of cognitive biases, analogous to mutation—and examine its consequences. Our results show that this process produces convergence towards systems of colour terms similar to those seen across human languages, providing support for the conclusion that the effects of cognitive biases, brought out through cultural transmission, can account for universals in colour naming. PMID:23486436
Zou, Keshu; Zhang, Dianchang; Guo, Huayang; Zhu, Caiyan; Li, Min; Jiang, Shigui
2014-05-25
Pearl oyster Pinctada fucata is widely cultured to produce seawater pearl in South China, and the quality of pearl is significantly affected by its shell color. Thus the Pearl Oyster Selective Breeding Program (POSBP) was carried out for the shell color and growth traits. The black (B), gold (G), red (R) and white (W) shell strains with fast growth trait were achieved after five successive generation selection. In this study, AFLP technique was used to scan genome of four strains with different shell colors to identify the candidate markers under artificial selection. Eight AFLP primer combinations were screened and yielded 688 loci, 676 (98.26%) of which were polymorphic. In black, gold, red and white strains, the percentage of polymorphic loci was 90.41%, 87.79%, 93.60% and 93.31%, respectively, Nei's gene diversity was 0.3225, 0.2829, 0.3221 and 0.3292, Shannon's information index was 0.4801, 0.4271, 0.4825 and 0.4923, and the value of FST was 0.1805. These results suggested that the four different shell color strains had high genetic diversity and great genetic differentiation among strains, which had been subjected to the continuous selective pressures during the artificial selective breeding. Furthermore, six outlier loci were considered as the candidate markers under artificial selection for shell color. This study provides a molecular evidence for the inheritance of shell color of P. fucata. Copyright © 2014 Elsevier B.V. All rights reserved.
Preston, K P; Higham, S M; Smith, P W
2007-06-01
The efficacy of three techniques for the disinfection of artificial sub-surface root caries lesions and their response to subsequent episodes of de- and remineralization was investigated quantitatively in vitro. Sub-surface dentinal lesions (n=20), cut into four experimental blocks and deliberately contaminated with Streptococcus mutans, were subject to either steam autoclaving (121 degrees C, 5min), gamma irradiation (4100Gy), immersion in 0.1% (w/v) thymol-distilled water solution (24h) or reserved as a control. Next, the lesions were incubated aerobically in sterile nutrient broth for 24h at 37 degrees C and resultant cultures plated onto blood agar and neutralisation agar. Ten blocks from each experimental group were then immersed in an acidic buffer solution or exposed to artificial saliva for 5 days. Baseline changes in the mineral content and distribution of the lesions were assessed by transverse microradiography (TMR). Micro-organisms were recovered from each control block and one block treated by gamma irradiation. Steam autoclaving and immersion in a thymol solution significantly decreased (p<0.05) the amount of mineral lost from the body of lesions subject to a further acid challenge. Mineral ion uptake by lesions exposed to artificial saliva was significantly increased (p<0.05) through disinfection by steam autoclaving. Gamma irradiation proved the most acceptable method for the disinfection of sub-surface root dentine lesions having the least adverse effect on demineralization and remineralization.
Calin Popovici (1910-1977): The Founder of Modern Astrophysics in Romania
NASA Astrophysics Data System (ADS)
Dumitrescu, A.; Maris, G.
2007-03-01
Connected to the development of astrophysics at the world level, animated by the wish to create a Romanian school of astrophysics and getting understanding and support from the director of the Observatory, the academician Gheorghe Demetrescu, Prof. Calin Popovici laid the basis of the new sector of solar researches, whose coordinator he became in 1955. After the launch of the first artificial satellite on 4 October 1957, Prof. C. Popovici, anticipating the importance of space research in the future, organized at Bucharest Observatory one of the first artificial satellites tracking station in Europe. Later, the group of artificial satellites was set up, whose research focused especially on two new research fields: cosmic triangulation and the study of high atmosphere by means of artificial satellites. It was also at the initiative of Prof. Popovici that in 1962 the second pavilion (after the solar one) was built and was endowed with the new Cassegrain telescope (50/750 cm) equipped with a high precision photoelectric photometer. Thus, the new research sector dedicated to variable stars study was set up. Due to his high professionalism, abnegation and passion for astronomy, Prof. C. Popovici managed to overcome some political difficulties, and his dream of creating a section of astrophysics had come true. Prof. C. Popovici had also an exceptional merit in the scientific training of his collaborators. His vast activity carried out throughout the years in the service of astronomy, education and culture was rewarded with the distinction of academician granted post-mortem.
Artificial insect wings of diverse morphology for flapping-wing micro air vehicles.
Shang, J K; Combes, S A; Finio, B M; Wood, R J
2009-09-01
The development of flapping-wing micro air vehicles (MAVs) demands a systematic exploration of the available design space to identify ways in which the unsteady mechanisms governing flapping-wing flight can best be utilized for producing optimal thrust or maneuverability. Mimicking the wing kinematics of biological flight requires examining the potential effects of wing morphology on flight performance, as wings may be specially adapted for flapping flight. For example, insect wings passively deform during flight, leading to instantaneous and potentially unpredictable changes in aerodynamic behavior. Previous studies have postulated various explanations for insect wing complexity, but there lacks a systematic approach for experimentally examining the functional significance of components of wing morphology, and for determining whether or not natural design principles can or should be used for MAVs. In this work, a novel fabrication process to create centimeter-scale wings of great complexity is introduced; via this process, a wing can be fabricated with a large range of desired mechanical and geometric characteristics. We demonstrate the versatility of the process through the creation of planar, insect-like wings with biomimetic venation patterns that approximate the mechanical properties of their natural counterparts under static loads. This process will provide a platform for studies investigating the effects of wing morphology on flight dynamics, which may lead to the design of highly maneuverable and efficient MAVs and insight into the functional morphology of natural wings.
Contingency rescheduling of spacecraft operations
NASA Technical Reports Server (NTRS)
Britt, Daniel L.; Geoffroy, Amy L.; Gohring, John R.
1988-01-01
Spacecraft activity scheduling was a focus of attention in artificial intelligence recently. Several scheduling systems were devised which more-or-less successfully address various aspects of the activity scheduling problem, though most of these are not yet mature, with the notable expection of NASA's ESP. Few current scheduling systems, however, make any attempt to deal fully with the problem of modifying a schedule in near-real-time in the event of contingencies which may arise during schedule execution. These contingencies can include resources becoming unavailable unpredictably, a change in spacecraft conditions or environment, or the need to perform an activity not scheduled. In these cases it becomes necessary to repair an existing schedule, disrupting ongoing operations as little as possible. Normal scheduling is just a part of that which must be accomplished during contingency rescheduling. A prototype system named MAESTRO was developed for spacecraft activity scheduling. MAESTRO is briefly described with a focus on recent work in the area of real-time contingency handling. Included is a discussion of some of the complexities of the scheduling problem and how they affect contingency rescheduling, such as temporal constraints between activities, activities which may be interrupted and continued in any of several ways, and different ways to choose a resource complement which will allow continuation of an activity. Various heuristics used in MAESTRO for contingency rescheduling is discussed, as are operational concerns such as interaction of the scheduler with spacecraft subsystems controllers.
Fiori, Stefano; Scherm, Barbara; Liu, Jia; Farrell, Robert; Mannazzu, Ilaria; Budroni, Marilena; Maserti, Bianca E; Wisniewski, Michael E; Migheli, Quirico
2012-11-01
Pichia fermentans (strain DISAABA 726) is an effective biocontrol agent against Monilinia fructicola and Botrytis cinerea when inoculated in artificially wounded apple fruit but is an aggressive pathogen when inoculated on wounded peach fruit, causing severe fruit decay. Pichia fermentans grows as budding yeast on apple tissue and exhibits pseudohyphal growth on peach tissue, suggesting that dimorphism may be associated with pathogenicity. Two complementary suppressive subtractive hybridization (SSH) strategies, that is, rapid subtraction hybridization (RaSH) and PCR-based subtraction, were performed to identify genes differentially expressed by P. fermentans after 24-h growth on apple vs. peach fruit. Gene products that were more highly expressed on peach than on apple tissue, or vice versa, were sequenced and compared with available yeast genome sequence databases. Several of the genes more highly expressed, when P. fermentans was grown on peach, were related to stress response, glycolysis, amino acid metabolism, and alcoholic fermentation but surprisingly not to cell wall degrading enzymes such as pectinases or cellulases. The dual activity of P. fermentans as both a biocontrol agent and a pathogen emphasizes the need for a thorough risk analysis of potential antagonists to avoid unpredictable results that could negatively impact the safe use of postharvest biocontrol strategies. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.
Language learning, language use and the evolution of linguistic variation
Perfors, Amy; Fehér, Olga; Samara, Anna; Swoboda, Kate; Wonnacott, Elizabeth
2017-01-01
Linguistic universals arise from the interaction between the processes of language learning and language use. A test case for the relationship between these factors is linguistic variation, which tends to be conditioned on linguistic or sociolinguistic criteria. How can we explain the scarcity of unpredictable variation in natural language, and to what extent is this property of language a straightforward reflection of biases in statistical learning? We review three strands of experimental work exploring these questions, and introduce a Bayesian model of the learning and transmission of linguistic variation along with a closely matched artificial language learning experiment with adult participants. Our results show that while the biases of language learners can potentially play a role in shaping linguistic systems, the relationship between biases of learners and the structure of languages is not straightforward. Weak biases can have strong effects on language structure as they accumulate over repeated transmission. But the opposite can also be true: strong biases can have weak or no effects. Furthermore, the use of language during interaction can reshape linguistic systems. Combining data and insights from studies of learning, transmission and use is therefore essential if we are to understand how biases in statistical learning interact with language transmission and language use to shape the structural properties of language. This article is part of the themed issue ‘New frontiers for statistical learning in the cognitive sciences’. PMID:27872370
Reducing false negatives in clinical practice: the role of neural network technology.
Mango, L J
1996-10-01
The fact that some cervical smears result in false-negative findings is an unavoidable and unpredictable consequence of the conventional (manual microscopic) method of screening. Errors in the detection and interpretation of abnormality are cited as leading causes of false-negative cytology findings; these are random errors that are not known to correlate with any patient risk factor, which makes the false-negative findings a "silent" threat that is difficult to prevent. Described by many as a labor-intensive procedure, the microscopic evaluation of a cervical smear involves a detailed search among hundreds of thousands of cells on each smear for a possible few that may indicate abnormality. Investigations into causes of false-negative findings preceding the discovery of high-grade lesions found that many smears had very few diagnostic cells that were often very small in size. These small cells were initially overlooked or misinterpreted and repeatedly missed on rescreening. PAPNET testing is designed to supplement conventional screening by detecting abnormal cells that initially may have been missed by microscopic examination. This interactive system uses neural networks, a type of artificial intelligence well suited for pattern recognition, to automate the arduous search for abnormality. The instrument focuses the review of suspicious cells by a trained cytologist. Clinical studies indicate that PAPNET testing is sensitive to abnormality typically missed by conventional screening and that its use as a supplemental test improves the accuracy of screening.
de Bruijn, Robert; Romero, L Michael
2013-03-01
Free-roaming animals continually cope with changes in their environment. One of the most unpredictable environmental phenomena is weather. Being able to respond to weather appropriately is crucial as it can be a threat to survival. The stress response, consisting of increases in heart rate and release of glucocorticoids, is an important mechanism by which animals cope with stressors. This study examined behavioral, heart rate, and corticosterone responses of captive European starlings (Sturnus vulgaris) to two aspects of weather mimicked under controlled conditions, a subtle (3 °C) decrease in temperature and a short, mild bout of rain. Both decreased temperature and exposure to rain elicited increases in heart rate and corticosterone in non-molting starlings. Molt is an important life history stage in birds that affects feather cover and may require a different response to weather-related stressors. We repeated the experiment in molting starlings and found increases in heart rate in response to rain and cold wind. However, the hypothalamic-pituitary-adrenal (HPA)-axis was suppressed during molt, as molting starlings did not increase corticosterone release in response to either stimulus. These data suggest these stimuli induce increased allostatic load in starlings, and that animals may adjust their response depending on the life-history stage. Copyright © 2012 Elsevier Inc. All rights reserved.
Language learning, language use and the evolution of linguistic variation.
Smith, Kenny; Perfors, Amy; Fehér, Olga; Samara, Anna; Swoboda, Kate; Wonnacott, Elizabeth
2017-01-05
Linguistic universals arise from the interaction between the processes of language learning and language use. A test case for the relationship between these factors is linguistic variation, which tends to be conditioned on linguistic or sociolinguistic criteria. How can we explain the scarcity of unpredictable variation in natural language, and to what extent is this property of language a straightforward reflection of biases in statistical learning? We review three strands of experimental work exploring these questions, and introduce a Bayesian model of the learning and transmission of linguistic variation along with a closely matched artificial language learning experiment with adult participants. Our results show that while the biases of language learners can potentially play a role in shaping linguistic systems, the relationship between biases of learners and the structure of languages is not straightforward. Weak biases can have strong effects on language structure as they accumulate over repeated transmission. But the opposite can also be true: strong biases can have weak or no effects. Furthermore, the use of language during interaction can reshape linguistic systems. Combining data and insights from studies of learning, transmission and use is therefore essential if we are to understand how biases in statistical learning interact with language transmission and language use to shape the structural properties of language.This article is part of the themed issue 'New frontiers for statistical learning in the cognitive sciences'. © 2016 The Authors.
Changed Synaptic Plasticity in Neural Circuits of Depressive-Like and Escitalopram-Treated Rats
Li, Xiao-Li; Yuan, Yong-Gui; Xu, Hua; Wu, Di; Gong, Wei-Gang; Geng, Lei-Yu; Wu, Fang-Fang; Tang, Hao; Xu, Lin
2015-01-01
Background: Although progress has been made in the detection and characterization of neural plasticity in depression, it has not been fully understood in individual synaptic changes in the neural circuits under chronic stress and antidepressant treatment. Methods: Using electron microscopy and Western-blot analyses, the present study quantitatively examined the changes in the Gray’s Type I synaptic ultrastructures and the expression of synapse-associated proteins in the key brain regions of rats’ depressive-related neural circuit after chronic unpredicted mild stress and/or escitalopram administration. Meanwhile, their depressive behaviors were also determined by several tests. Results: The Type I synapses underwent considerable remodeling after chronic unpredicted mild stress, which resulted in the changed width of the synaptic cleft, length of the active zone, postsynaptic density thickness, and/or synaptic curvature in the subregions of medial prefrontal cortex and hippocampus, as well as the basolateral amygdaloid nucleus of the amygdala, accompanied by changed expression of several synapse-associated proteins. Chronic escitalopram administration significantly changed the above alternations in the chronic unpredicted mild stress rats but had little effect on normal controls. Also, there was a positive correlation between the locomotor activity and the maximal synaptic postsynaptic density thickness in the stratum radiatum of the Cornu Ammonis 1 region and a negative correlation between the sucrose preference and the length of the active zone in the basolateral amygdaloid nucleus region in chronic unpredicted mild stress rats. Conclusion: These findings strongly indicate that chronic stress and escitalopram can alter synaptic plasticity in the neural circuits, and the remodeled synaptic ultrastructure was correlated with the rats’ depressive behaviors, suggesting a therapeutic target for further exploration. PMID:25899067
Ortiz, J Bryce; Taylor, Sara B; Hoffman, Ann N; Campbell, Alyssa N; Lucas, Louis R; Conrad, Cheryl D
2015-04-01
Chronic restraint stress alters hippocampal-dependent spatial learning and memory in a sex-dependent manner, impairing spatial performance in male rats and leaving intact or facilitating performance in female rats. Moreover, these stress-induced spatial memory deficits improve following post-stress recovery in males. The current study examined whether restraint administered in an unpredictable manner would eliminate these sex differences and impact a post-stress period on spatial ability and limbic glutamic acid decarboxylase (GAD65) expression. Male (n=30) and female (n=30) adult Sprague-Dawley rats were assigned to non-stressed control (Con), chronic stress (Str-Imm), or chronic stress given a post-stress recovery period (Str-Rec). Stressed rats were unpredictably restrained for 21 days using daily non-repeated combinations of physical context, duration, and time of day. Then, all rats were tested on the radial arm water maze (RAWM) for 2 days and given one retention trial on the third day, with brains removed 30min later to assess GAD65 mRNA. In Str-Imm males, deficits occurred on day 1 of RAWM acquisition, an impairment that was not evident in the Str-Rec group. In contrast, females did not show significant outcomes following chronic stress or post-stress recovery. In males, amygdalar GAD65 expression negatively correlated with RAWM performance on day 1. In females, hippocampal CA1 GAD65 positively correlated with RAWM performance on day 1. These results demonstrate that GABAergic function may contribute to the sex differences observed following chronic stress. Furthermore, unpredictable restraint and a recovery period failed to eliminate the sex differences on spatial learning and memory. Copyright © 2014 Elsevier B.V. All rights reserved.
Ortiz, J. Bryce; Taylor, Sara B.; Hoffman, Ann N.; Campbell, Alyssa N.; Lucas, Louis R.; Conrad, Cheryl D.
2015-01-01
Chronic restraint stress alters hippocampal-dependent spatial learning and memory in a sex-dependent manner, impairing spatial performance in male rats and leaving intact or facilitating performance in female rats. Moreover, these stress-induced spatial memory deficits improve following post-stress recovery in males. The current study examined whether restraint administered in an unpredictable manner would eliminate these sex differences and impact a post-stress period on spatial ability and limbic glutamic acid decarboxylase (GAD65) expression. Male (n=30) and female (n=30) adult Sprague-Dawley rats were assigned to non-stressed control (Con), chronic stress (Str-Imm), or chronic stress given a post-stress recovery period (Str-Rec). Stressed rats were unpredictably restrained for 21 days using daily non-repeated combinations of physical context, duration, and time of day. Then, all rats were tested on the radial arm water maze (RAWM) for two days and given one retention trial on the third day, with brains removed 30 minutes later to assess GAD65 mRNA. In Str-Imm males, deficits occurred on day 1 of RAWM acquisition, an impairment that was not evident in the Str-Rec group. In contrast, females did not show significant outcomes following chronic stress or post-stress recovery. In males, amygdalar GAD65 expression negatively correlated with RAWM performance on day 1. In females, hippocampal CA1 GAD65 positively correlated with RAWM performance on day 1. These results demonstrate that GABAergic function may contribute to the sex differences observed following chronic stress. Furthermore, unpredictable restraint and a recovery period failed to eliminate the sex differences on spatial learning and memory. PMID:25591480
Sugimoto, Fumie; Kimura, Motohiro; Takeda, Yuji; Katayama, Jun'ichi
2017-08-16
In a three-stimulus oddball task, the amplitude of P3a elicited by deviant stimuli increases with an increase in the difficulty of discriminating between standard and target stimuli (i.e. task-difficulty effect on P3a), indicating that attentional capture by deviant stimuli is enhanced with an increase in task difficulty. This enhancement of attentional capture may be explained in terms of the modulation of modality-nonspecific temporal attention; that is, the participant's attention directed to the predicted timing of stimulus presentation is stronger when the task difficulty increases, which results in enhanced attentional capture. The present study examined this possibility with a modified three-stimulus oddball task consisting of a visual standard, a visual target, and four types of deviant stimuli defined by a combination of two modalities (visual and auditory) and two presentation timings (predicted and unpredicted). We expected that if the modulation of temporal attention is involved in enhanced attentional capture, then the task-difficulty effect on P3a should be reduced for unpredicted compared with predicted deviant stimuli irrespective of their modality; this is because the influence of temporal attention should be markedly weaker for unpredicted compared with predicted deviant stimuli. The results showed that the task-difficulty effect on P3a was significantly reduced for unpredicted compared with predicted deviant stimuli in both the visual and the auditory modalities. This result suggests that the modulation of modality-nonspecific temporal attention induced by the increase in task difficulty is at least partly involved in the enhancement of attentional capture by deviant stimuli.
Bacterial Artificial Chromosome Clones of Viruses Comprising the Towne Cytomegalovirus Vaccine
Cui, Xiaohong; Adler, Stuart P.; Davison, Andrew J.; Smith, Larry; Habib, EL-Sayed E.; McVoy, Michael A.
2012-01-01
Bacterial artificial chromosome (BAC) clones have proven invaluable for genetic manipulation of herpesvirus genomes. BAC cloning can also be useful for capturing representative genomes that comprise a viral stock or mixture. The Towne live attenuated cytomegalovirus vaccine was developed in the 1970s by serial passage in cultured fibroblasts. Although its safety, immunogenicity, and efficacy have been evaluated in nearly a thousand human subjects, the vaccine itself has been little studied. Instead, genetic composition and in vitro growth properties have been inferred from studies of laboratory stocks that may not always accurately represent the viruses that comprise the vaccine. Here we describe the use of BAC cloning to define the genotypic and phenotypic properties of viruses from the Towne vaccine. Given the extensive safety history of the Towne vaccine, these BACs provide a logical starting point for the development of next-generation rationally engineered cytomegalovirus vaccines. PMID:22187535
Iao, Lai-Sang; Ng, Lai Yan; Wong, Anita Mei Yin; Lee, Oi Ting
2017-03-01
This study investigated nonadjacent dependency learning in Cantonese-speaking children with and without a history of specific language impairment (SLI) in an artificial linguistic context. Sixteen Cantonese-speaking children with a history of SLI and 16 Cantonese-speaking children with typical language development (TLD) were tested with a nonadjacent dependency learning task using artificial languages that mimic Cantonese. Children with TLD performed above chance and were able to discriminate between trained and untrained nonadjacent dependencies. However, children with a history of SLI performed at chance and were not able to differentiate trained versus untrained nonadjacent dependencies. These findings, together with previous findings from English-speaking adults and adolescents with language impairments, suggest that individuals with atypical language development, regardless of age, diagnostic status, language, and culture, show difficulties in learning nonadjacent dependencies. This study provides evidence for early impairments to statistical learning in individuals with atypical language development.
Liu, Yongding; Cockell, Charles S; Wang, Gaohong; Hu, Chunxiang; Chen, Lanzhou; De Philippis, Roberto
2008-02-01
Studies on the colonization of environmentally extreme ground surfaces were conducted in a Mars-like desert area of Inner Mongolia, People's Republic of China, with microalgae and cyanobacteria. We collected and mass-cultured cyanobacterial strains from these regions and investigated their ability to form desert crusts artificially. These crusts had the capacity to resist sand wind erosion after just 15 days of growth. Similar to the surface of some Chinese deserts, the surface of Mars is characterized by a layer of fine dust, which will challenge future human exploration activities, particularly in confined spaces that will include greenhouses and habitats. We discuss the use of such crusts for the local control of desert sands in enclosed spaces on Mars. These experiments suggest innovative new directions in the applied use of microbe-mineral interactions to advance the human exploration and settlement of space.
Bacterial artificial chromosome clones of viruses comprising the towne cytomegalovirus vaccine.
Cui, Xiaohong; Adler, Stuart P; Davison, Andrew J; Smith, Larry; Habib, El-Sayed E; McVoy, Michael A
2012-01-01
Bacterial artificial chromosome (BAC) clones have proven invaluable for genetic manipulation of herpesvirus genomes. BAC cloning can also be useful for capturing representative genomes that comprise a viral stock or mixture. The Towne live attenuated cytomegalovirus vaccine was developed in the 1970s by serial passage in cultured fibroblasts. Although its safety, immunogenicity, and efficacy have been evaluated in nearly a thousand human subjects, the vaccine itself has been little studied. Instead, genetic composition and in vitro growth properties have been inferred from studies of laboratory stocks that may not always accurately represent the viruses that comprise the vaccine. Here we describe the use of BAC cloning to define the genotypic and phenotypic properties of viruses from the Towne vaccine. Given the extensive safety history of the Towne vaccine, these BACs provide a logical starting point for the development of next-generation rationally engineered cytomegalovirus vaccines.
Gago, Jorge; Landín, Mariana; Gallego, Pedro Pablo
2010-10-15
This study employs artificial neural networks (ANNs) to create a model to identify relationships between variables affecting the in vitro rhizogenesis and acclimatization of two cultivars of Vitis vinifera L. Albariño and Mencía. The effects of three factors (inputs), the type of cultivar, concentration and exposure time to indolebutyric acid (IBA), on the success of in vitro rhizogenesis and acclimatization were evaluated. The developed model, using ANNs software, was assessed using a separate set of validation data and was in good agreement with the observed results. Exposure time to IBA was found to have the dominant role in influencing the height of acclimatized plantlets. ANNs can be a useful tool for modeling different complex processes and data sets, in plant tissue cultures or, more generally, in plant biology. Copyright (c) 2010 Elsevier GmbH. All rights reserved.
Magnesium degradation as determined by artificial neural networks.
Willumeit, Regine; Feyerabend, Frank; Huber, Norbert
2013-11-01
Magnesium degradation under physiological conditions is a highly complex process in which temperature, the use of cell culture growth medium and the presence of CO2, O2 and proteins can influence the corrosion rate and the composition of the resulting corrosion layer. Due to the complexity of this process it is almost impossible to predict the parameters that are most important and whether some parameters have a synergistic effect on the corrosion rate. Artificial neural networks are a mathematical tool that can be used to approximate and analyse non-linear problems with multiple inputs. In this work we present the first analysis of corrosion data obtained using this method, which reveals that CO2 and the composition of the buffer system play a crucial role in the corrosion of magnesium, whereas O2, proteins and temperature play a less prominent role. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Nature or Artifice? Grafting in Early Modern Surgery and Agronomy.
Savoia, Paolo
2017-01-01
In 1597, Gaspare Tagliacozzi published a famous two-volume book on “plastic surgery.” The reconstructive technique he described was based on grafting skin taken from the arm onto the mutilated parts of the patient's damaged face – especially noses. This paper focuses on techniques of grafting, the “culture of grafting,” and the relationships between surgery and plant sciences in the sixteenth century. By describing the fascination with grafting in surgery, natural history, gardening, and agronomy the paper argues that grafting techniques were subject to delicate issues: to what extent it was morally acceptable to deceive the eye with artificial entities? and what was the status of the product of a surgical procedure that challenged the traditional natural/artificial distinction? Finally, this paper shows how in the seventeenth century grafting survived the crisis of Galenism by discussing the role it played in teratology and in controversies on the uses the new mechanistic anatomy.
Efficient transformation and artificial miRNA gene silencing in Lemna minor
Cantó-Pastor, Alex; Mollá-Morales, Almudena; Ernst, Evan; Dahl, William; Zhai, Jixian; Yan, Yiheng; Meyers, Blake; Shanklin, John; Martienssen, Robert
2015-01-01
Lack of genetic tools in the Lemnaceae (duckweed) has impeded full implementation of this organism as model for biological research, despite its rapid doubling time, simple architecture and unusual metabolic characteristics. Here we present technologies to facilitate high-throughput genetic studies in duckweed. We developed a fast and efficient method for producing Lemna minor stable transgenic fronds via agrobacterium-mediated transformation and regeneration from tissue culture. Additionally, we engineered an artificial microRNA (amiRNA) gene silencing system. We identified a Lemna gibba endogenous miR166 precursor and used it as a backbone to produce amiRNAs. As a proof of concept we induced the silencing of CH42, a Magnesium Chelatase subunit, using our amiRNA platform. Expression of CH42 in transgenic Lemna minor fronds was significantly reduced, which resulted in reduction of chlorophyll pigmentation. The techniques presented here will enable tackling future challenges in the biology and biotechnology of Lemnaceae. PMID:24989135
Hanlon, Shane D.; Neves, Richard J.
2006-01-01
Recent efforts to restore remnant or extirpated populations of freshwater mussels have focused on artificial propagation as an effective and practical conservation strategy. Although artificially cultured juveniles have been produced and released to the wild at various times of the year, no study has investigated the best time of year to release these juveniles. Newly metamorphosed juveniles of the wavyrayed lampmussel (Lampsilis fasciola) were released into a stream-fed fish hatchery raceway during March, June, and September. Growth and survival rates were measured 32, 52, 72, and 92 days post-metamorphosis. Juveniles released in June experienced the greatest growth and survival rates. Juveniles released in September and March experienced high mortality within the first month of release and exhibited poor growth in the cool water conditions typical of those seasons. Overwinter survival exhibited a size-dependent relationship.
Venkateswarulu, T C; Prabhakar, K Vidya; Kumar, R Bharath; Krupanidhi, S
2017-07-01
Modeling and optimization were performed to enhance production of lactase through submerged fermentation by Bacillus subtilis VUVD001 using artificial neural networks (ANN) and response surface methodology (RSM). The effect of process parameters namely temperature (°C), pH, and incubation time (h) and their combinational interactions on production was studied in shake flask culture by Box-Behnken design. The model was validated by conducting an experiment at optimized process variables which gave the maximum lactase activity of 91.32 U/ml. Compared to traditional activity, 3.48-folds improved production was obtained after RSM optimization. This study clearly shows that both RSM and ANN models provided desired predictions. However, compared with RSM (R 2 = 0.9496), the ANN model (R 2 = 0.99456) gave a better prediction for the production of lactase.
A gelatin composite scaffold strengthened by drug-loaded halloysite nanotubes.
Ji, Lijun; Qiao, Wei; Zhang, Yuheng; Wu, Huayu; Miao, Shiyong; Cheng, Zhilin; Gong, Qianming; Liang, Ji; Zhu, Aiping
2017-09-01
Mechanical properties and anti-infection are two of the most concerned issues for artificial bone grafting materials. Bone regeneration porous scaffolds with sustained drug release were developed by freeze-drying the mixture of nanosized drug-loaded halloysite nanotubes (HNTs) and gelatin. The scaffolds showed porous structure and excellent biocompatibility. The mechanical properties of the obtained composite scaffolds were enhanced significantly by HNTs to >300%, comparing to those of gelatin scaffold, and match to those of natural cancellous bones. The ibuprofen-loaded HNTs incorporated in the scaffolds allowed extended drug release over 100h, comparing to 8h when directly mixed the drug into the gelatin scaffold. The biological properties of the composite scaffolds were investigated by culturing MG63 cells on them. The HNTs/gelatin scaffolds with excellent mechanical properties and sustained drug release could be a promising artificial bone grating material. Copyright © 2017 Elsevier B.V. All rights reserved.
Bacteria facilitate prey retention by the pitcher plant Darlingtonia californica.
Armitage, David W
2016-11-01
Bacteria are hypothesized to provide a variety of beneficial functions to plants. Many carnivorous pitcher plants, for example, rely on bacteria for digestion of captured prey. This bacterial community may also be responsible for the low surface tensions commonly observed in pitcher plant digestive fluids, which might facilitate prey capture. I tested this hypothesis by comparing the physical properties of natural pitcher fluid from the pitcher plant Darlingtonia californica and cultured 'artificial' pitcher fluids and tested these fluids' prey retention capabilities. I found that cultures of pitcher leaves' bacterial communities had similar physical properties to raw pitcher fluids. These properties facilitated the retention of insects by both fluids and hint at a previously undescribed class of plant-microbe interaction. © 2016 The Author(s).
Cellular Analysis of Adult Neural Stem Cells for Investigating Prion Biology.
Haigh, Cathryn L
2017-01-01
Traditional primary and secondary cell cultures have been used for the investigation of prion biology and disease for many years. While both types of cultures produce highly valid and immensely valuable results, they also have their limitations; traditional cell lines are often derived from cancers, therefore subject to numerous DNA changes, and primary cultures are labor-intensive and expensive to produce requiring sacrifice of many animals. Neural stem cell (NSC) cultures are a relatively new technology to be used for the study of prion biology and disease. While NSCs are subject to their own limitations-they are generally cultured ex vivo in environments that artificially force their growth-they also have their own unique advantages. NSCs retain the ability for self-renewal and can therefore be propagated in culture similarly to secondary cultures without genetic manipulation. In addition, NSCs are multipotent; they can be induced to differentiate into mature cells of central nervous system (CNS) linage. The combination of self-renewal and multipotency allows NSCs to be used as a primary cell line over multiple generations saving time, costs, and animal harvests, thus providing a valuable addition to the existing cell culture repertoire used for investigation of prion biology and disease. Furthermore, NSC cultures can be generated from mice of any genotype, either by embryonic harvest or harvest from adult brain, allowing gene expression to be studied without further genetic manipulation. This chapter describes a standard method of culturing adult NSCs and assays for monitoring NSC growth, migration, and differentiation and revisits basic reactive oxygen species detection in the context of NSC cultures.
Zeale, Matt R. K.; Bennitt, Emily; Newson, Stuart E.; Packman, Charlotte; Browne, William J.; Harris, Stephen; Jones, Gareth; Stone, Emma
2016-01-01
Bats frequently roost in historic churches, and these colonies are of considerable conservation value. Inside churches, bat droppings and urine can cause damage to the historic fabric of the building and to items of cultural significance. In extreme cases, large quantities of droppings can restrict the use of a church for worship and/or other community functions. In the United Kingdom, bats and their roosts are protected by law, and striking a balance between conserving the natural and cultural heritage can be a significant challenge. We investigated mitigation strategies that could be employed in churches and other historic buildings to alleviate problems caused by bats without adversely affecting their welfare or conservation status. We used a combination of artificial roost provision and deterrence at churches in Norfolk, England, where significant maternity colonies of Natterer’s bats Myotis nattereri damage church features. Radio-tracking data and population modelling showed that excluding M. nattereri from churches is likely to have a negative impact on their welfare and conservation status, but that judicious use of deterrents, especially high intensity ultrasound, can mitigate problems caused by bats. We show that deterrence can be used to move bats humanely from specific roosting sites within a church and limit the spread of droppings and urine so that problems to congregations and damage to cultural heritage can be much reduced. In addition, construction of bespoke roost spaces within churches can allow bats to continue to roost within the fabric of the building without flying in the church interior. We highlight that deterrence has the potential to cause serious harm to M. nattereri populations if not used judiciously, and so the effects of deterrents will need careful monitoring, and their use needs strict regulation. PMID:26771548
Matsumura, Hajime; Matsushima, Asako; Ueyama, Masashi; Kumagai, Norio
2016-06-01
In the 1970s, Green et al. developed a method that involved culturing keratinocyte sheets and used for treatment of burns. Since then, the take rate of cultured epidermal autograft (CEA) onto fascia, granulation tissue, or allografts has been extensively reported, while that on an artificial dermis in a large case series is not. Moreover, the contribution of CEA to patient survival has not been analyzed in a multicenter study. We conducted a 6-year multicenter surveillance on the application of the CEA "JACE(®") for treatment of burns >30% total body surface area (TBSA) across 118 Japanese hospitals. This surveillance included 216 patients and 718 graft sites for efficacy analysis. The CEA take rate at 4 weeks after grafting was evaluated, and safety was monitored until 52 weeks. In addition, the survival curve obtained in this study and the data obtained from the Tokyo Burn Unit Association (TBUA) were compared. The mean CEA take rates at week 4 were 66% (sites) and 68% (patients), and the rate on the artificial dermis was 65% for 226 sites. CEA application combined with wide split-thickness auto or patch autograft increased the CEA take rate. On comparison with the data obtained from the TBUA, which included data on individuals with burns of the same severity, CEA application was found to contribute to patient survival until 7 weeks after burn. We reported the take rate of CEA based on a 6-year multicenter surveillance. From our results, we found that the application of CEA is a useful treatment for the patients with extensive burns. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.
Strobel, H J; Russell, J B
1991-01-01
Washed cells of strain H18, a newly isolated ruminal selenomonad, decarboxylated succinate 25-fold faster than Selenomonas ruminantium HD4 (130 versus 5 nmol min-1 mg of protein-1, respectively). Batch cultures of strain H18 which were fermenting glucose did not utilize succinate, and glucose-limited continuous cultures were only able to decarboxylate significant amounts of succinate at slow (less than 0.1 h-1) dilution rates. Strain H18 grew more slowly on lactate than glucose (0.2 versus 0.4 h-1, respectively), and more than half of the lactate was initially converted to succinate. Succinate was only utilized after growth on lactate had ceased. Although nonenergized and glucose-energized cells had similar proton motive forces and ATP levels, glucose-energized cells were unable to transport succinate. Transport by nonenergized cells was decreased by small increases in osmotic strength, and it is possible that energy-dependent inhibition of succinate transport was related to changes in cell turgor. Since cells which were deenergized with 2-deoxyglucose or iodoacetate did not transport succinate, it appeared that glycogen metabolism was providing the driving force for succinate uptake. An artificial delta pH drove succinate transport in deenergized cells, but an artificial membrane potential (delta psi) could not serve as a driving force. Because succinate is nearly fully dissociated at pH 7.0 and the transport process was electroneutral, it appeared that succinate was taken up in symport with two protons. An Eadie-Hofstee plot indicated that the rate of uptake was unusually rapid at high substrate concentrations, but the low-velocity, high-affinity component could account for succinate utilization by stationary cultures.(ABSTRACT TRUNCATED AT 250 WORDS)
Li, Hui; Liu, Yanmei; Wang, Yuting; Chen, Meirong; Zhuang, Xiaoshan; Wang, Chaogang; Wang, Jiangxin; Hu, Zhangli
2018-01-01
Sulfur-deprived cultivation of Chlamydomonas reinhardtii , referred as "two-stage culture" transferring the cells from regular algal medium to sulfur-deplete one, has been extensively studied to improve photobio-H 2 production in this green microalga. During sulfur-deprivation treatment, the synthesis of a key component of photosystem II complex, D1 protein, was inhibited and improved photobio-H 2 production could be established in C. reinhardtii . However, separation of algal cells from a regular liquid culture medium to a sulfur-deprived one is not only a discontinuous process, but also a cost- and time-consuming operation. More applicable and economic alternatives for sustained H 2 production by C. reinhardtii are still highly required. In the present study, a significant improvement in photobio-H 2 production was observed in the transgenic green microalga C. reinhardtii , which employed a newly designed strategy based on a heat-inducible artificial miRNA (amiRNA) expression system targeting D1-encoded gene, psbA . A transgenic algal strain referred as "amiRNA-D1" has been successfully obtained by transforming the expression vector containing a heat-inducible promoter. After heat shock conducted in the same algal cultures, the expression of amiRNA-D1 was detected increased 15-fold accompanied with a 73% decrease of target gene psbA . More interestingly, this transgenic alga accumulated about 60% more H 2 content than the wild-type strain CC-849 at the end of 7-day cultivation. The photobio-H 2 production in the engineered transgenic alga was significantly improved. Without imposing any nutrient-deprived stress, this novel strategy provided a convenient and efficient way for regulation of photobio-H 2 production in green microalga by simply "turn on" the expression of a designed amiRNA.
NASA Technical Reports Server (NTRS)
Chakrabarti, Amitabha; Stoecker, Andrew; Schatten, Heide
1995-01-01
To explore the role of microgravity on cytoskeletal organization and skeletal calcium deposition during fertilization, cell division, and early development, the sea urchin was chosen as a model developmental system. Methods were developed to employ light, immunofluorescence, and electron microscopy on cultures being prepared for flight on the Space Shuttle. For analysis of microfilaments, microtubules, centrosomes, and calcium-requiring events, our standard laboratory protocols had to be modified substantially for experimentation on the Space Shuttle. All manipulations were carried out in a closed culture chamber containing 35 ml artificial sea water as a culture fluid. Unfertilized eggs stored for 24 hours in these chambers were fertilized with sperm diluted in sea water and fixed with concentrated fixatives for final fixation in formaldehyde, taxol, EGTA, and MgCl2(exp -6)H2O for 1 cell to 16 cell stages to preserve cytoskeletal structures for simultaneous analysis with light, immunofluorescence, and electron microscopy, and 1.5 percent glutaraldehyde and 0.4 percent formaldehyde for blastula and plueus stages. The fixed samples wre maintained in chambers without degradation for up to two weeks after which the specimens were processed and analyzed with routine methods. Since complex manipulations are not possible in the closed chambers, the fertilization coat was removed from fixation using 0.5 percent freshly prepared sodium thioglycolate solution at pH 10.0 which provided reliable immunofluorescence staining for microtubules. Sperm/egg fusion, mitosis, cytokinesis, and calcium deposition during spicule formatin in early embryogenesis were found to be without artificial alterations when compared to cells fixed fresh and processed with conventional methods.
Chemically grafted fibronectin for use in QCM-D cell studies
Sobolewski, Peter; Tomczyk, Nancy; Composto, Russell J.; Eckmann, David M.
2014-01-01
Traditionally, fibronectin has been used as a physisorbed surface coating (physFN) in cell culture experiments due to its critical role in cell adhesion. However, because the resulting layer is thick, unstable, and of unpredictable uniformity, this method of fibronectin deposition is unsuitable for some types of research, including quartz crystal microbalance (QCM) experiments involving cells. Here, we present a new method for chemical immobilization of fibronectin onto silicon oxide surfaces, including QCM crystals pre-coated with silicon oxide. We characterize these chemically coated fibronectin surfaces (chemFN) as well as physFN ones using surface ellipsometry (SE), Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), and contact angle measurements. A cell culture model demonstrates that cells on chemFN and physFN surfaces exhibit similar viability, structure, adhesion and metabolism. Finally, we perform QCM experiments using cells on both surfaces which demonstrate the superior suitability of chemFN coatings for QCM research, and provide real-time QCM-D data from cells subjected to an actin depolymerizing agent. Overall, our method of chemical immobilization of fibronectin yields great potential for furthering cellular experiments in which thin, stable and uniform coatings are desirable. As QCM research with cells has been rather limited in success thus far, we anticipate that this new technique will particularly benefit this experimental system by availing it to the much broader field of cell mechanics. PMID:24657645
Human papillomavirus in larynx.
Aaltonen, Leena-Maija; Rihkanen, Heikki; Vaheri, Antti
2002-04-01
The core of the present clinical and basic research knowledge of laryngeal human papillomavirus (HPV) infection is described. Review. A computer-aided search of MEDLINE database supplemented by hand searches of key journals was conducted. One of the tumor-promoting factors in the larynx is the HPV found both in normal laryngeal epithelium and in laryngeal tumors. The most important manifestation of laryngeal HPV infection is laryngeal papillomatosis, a rare disease caused by HPV types 6 and 11. In laryngeal carcinogenesis, the role of HPV remains uncertain. The means of transmission of HPV are partly unknown, and the course of laryngeal HPV infection is unpredictable and variable. Treatment of laryngeal papillomatosis is based on surgery, especially on CO2 laser and shaver. Alpha-interferon is the drug of choice in patients whose response to surgery is poor. However, neither interferon nor other antiviral drugs are able to eradicate the virus from laryngeal mucosa. Little is known about immunological mechanisms involved in laryngeal HPV infection, but in defense against HPV cellular immunity is considered a more important mechanism than humoral immunity. A good experimental model of HPV infection is lacking in which the entire viral life cycle can take place. Organotypic cell cultures (collagen rafts) are useful, but the rate-limiting step in this method is the difficulties in culturing HPV-positive epithelial cells. Although laryngeal papillomatosis is clinically well defined, the mechanisms and treatment modalities of laryngeal HPV infection need further investigations.
Tucker, Bram; Tsiazonera; Tombo, Jaovola; Hajasoa, Patricia; Nagnisaha, Charlotte
2015-01-01
A fact of life for farmers, hunter-gatherers, and fishermen in the rural parts of the world are that crops fail, wild resources become scarce, and winds discourage fishing. In this article we approach subsistence risk from the perspective of “coexistence thinking,” the simultaneous application of natural and supernatural causal models to explain subsistence success and failure. In southwestern Madagascar, the ecological world is characterized by extreme variability and unpredictability, and the cosmological world is characterized by anxiety about supernatural dangers. Ecological and cosmological causes seem to point to different risk minimizing strategies: to avoid losses from drought, flood, or heavy winds, one should diversify activities and be flexible; but to avoid losses caused by disrespected spirits one should narrow one’s range of behaviors to follow the code of taboos and offerings. We address this paradox by investigating whether southwestern Malagasy understand natural and supernatural causes as occupying separate, contradictory explanatory systems (target dependence), whether they make no categorical distinction between natural and supernatural forces and combine them within a single explanatory system (synthetic thinking), or whether they have separate natural and supernatural categories of causes that are integrated into one explanatory system so that supernatural forces drive natural forces (integrative thinking). Results from three field studies suggest that (a) informants explain why crops, prey, and market activities succeed or fail with reference to natural causal forces like rainfall and pests, (b) they explain why individual persons experience success or failure primarily with supernatural factors like God and ancestors, and (c) they understand supernatural forces as driving natural forces, so that ecology and cosmology represent distinct sets of causes within a single explanatory framework. We expect that future cross-cultural analyses may find that this form of “integrative thinking” is common in unpredictable environments and is a cognitive strategy that accompanies economic diversification. PMID:26528205
Tucker, Bram; Tsiazonera; Tombo, Jaovola; Hajasoa, Patricia; Nagnisaha, Charlotte
2015-01-01
A fact of life for farmers, hunter-gatherers, and fishermen in the rural parts of the world are that crops fail, wild resources become scarce, and winds discourage fishing. In this article we approach subsistence risk from the perspective of "coexistence thinking," the simultaneous application of natural and supernatural causal models to explain subsistence success and failure. In southwestern Madagascar, the ecological world is characterized by extreme variability and unpredictability, and the cosmological world is characterized by anxiety about supernatural dangers. Ecological and cosmological causes seem to point to different risk minimizing strategies: to avoid losses from drought, flood, or heavy winds, one should diversify activities and be flexible; but to avoid losses caused by disrespected spirits one should narrow one's range of behaviors to follow the code of taboos and offerings. We address this paradox by investigating whether southwestern Malagasy understand natural and supernatural causes as occupying separate, contradictory explanatory systems (target dependence), whether they make no categorical distinction between natural and supernatural forces and combine them within a single explanatory system (synthetic thinking), or whether they have separate natural and supernatural categories of causes that are integrated into one explanatory system so that supernatural forces drive natural forces (integrative thinking). Results from three field studies suggest that (a) informants explain why crops, prey, and market activities succeed or fail with reference to natural causal forces like rainfall and pests, (b) they explain why individual persons experience success or failure primarily with supernatural factors like God and ancestors, and (c) they understand supernatural forces as driving natural forces, so that ecology and cosmology represent distinct sets of causes within a single explanatory framework. We expect that future cross-cultural analyses may find that this form of "integrative thinking" is common in unpredictable environments and is a cognitive strategy that accompanies economic diversification.
Chitosan-functionalized silk fibroin 3D scaffold for keratocyte culture.
Guan, Linan; Tian, Pei; Ge, Hongyan; Tang, Xianling; Zhang, Hong; Du, Lingling; Liu, Ping
2013-10-01
The goal of this study was to evaluate the potential suitability of an artificial membrane composed of silk fibroin (SF) functionalized by different ratios of chitosan (CS) as a substrate for the stroma of the cornea. Keratocytes were cultured on translucent membranes made of SF and CS with different ratios. The biophysical properties of the silk fibroin and chitosan (SF/CS) membrane were examined. The SF/CS showed tensile strengths that increased as the CS concentration increased, but the physical and mechanical properties of chitosan-functionalized silk fibroin scaffolds weakened significantly compared with those of native corneas. The resulting cell scaffolds were evaluated using western blot in addition to light and electron microscopy. The cell attachment and proliferation on the scaffold were similar to those on a plastic plate. Keratocytes cultured in serum on SF/CS exhibited stellate morphology along with a marked increase in the expression of keratocan compared with identical cultures on tissue culture plastics. The biocompatibility was tested by transplanting the acellular membrane into rabbit corneal stromal pockets. There was no inflammatory complication detected at any time point on the macroscopic level. Taken together, these results indicate that SF/CS holds promise as a substrate for corneal reconstruction.
Cultural Transmission and Evolution of Melodic Structures in Multi-generational Signaling Games.
Lumaca, Massimo; Baggio, Giosuè
2017-01-01
It has been proposed that languages evolve by adapting to the perceptual and cognitive constraints of the human brain, developing, in the course of cultural transmission, structural regularities that maximize or optimize learnability and ease of processing. To what extent would perceptual and cognitive constraints similarly affect the evolution of musical systems? We conducted an experiment on the cultural evolution of artificial melodic systems, using multi-generational signaling games as a laboratory model of cultural transmission. Signaling systems, using five-tone sequences as signals, and basic and compound emotions as meanings, were transmitted from senders to receivers along diffusion chains in which the receiver in each game became the sender in the next game. During transmission, structural regularities accumulated in the signaling systems, following principles of proximity, symmetry, and good continuation. Although the compositionality of signaling systems did not increase significantly across generations, we did observe a significant increase in similarity among signals from the same set. We suggest that our experiment tapped into the cognitive and perceptual constraints operative in the cultural evolution of musical systems, which may differ from the mechanisms at play in language evolution and change.
Hydrocortisone effect of arylsulfatase A in primary mouse brain cell cultures
DOE Office of Scientific and Technical Information (OSTI.GOV)
Marcelo, A.; Pieringer, R.A.
The primary goal of this study was to study the mechanism of action of hydrocortisone (HC) on arylsulfatase A (ASA) in primary cultures of cells that were dissociated from the brains of embryonic mice. Cells were cultured in a defined medium in the absence or in the presence of 3 ..mu..M HC. The specific activity of ASA in nontreated cells was 1.297 U/mg (U = ..mu..mol/hr) while the value for the HC-treated cells was 0.783 U/mg. The authors data shows that HC inhibits ASA activity in these cultures cells (p < 0.001). The determination of the ASA enzyme activity wasmore » assayed primarily with the artificial substrate p-nitrocatechol sulfate. However, the natural substrate (cerebroside /sup 35/S-sulfate) also as active and correlated linearly with the activity of p-nitrocatechol sulfate. Purified ASA was isolated from calf brains and used to generate an antibody (Ab) against ASA. The specificity of the Ab for the ASA protein of cell cultures was tested in Ouchterlony double immunodiffusion studies. The Ab was used in a competitive enzyme-linked immunosorbent assay to quantify the number of ASA molecules in the cell extracts from the embryonic mouse cell cultures. Preliminary data suggest that HC decreases the number of ASA molecules.« less
Cultured meat from stem cells: challenges and prospects.
Post, Mark J
2012-11-01
As one of the alternatives for livestock meat production, in vitro culturing of meat is currently studied. The generation of bio-artificial muscles from satellite cells has been ongoing for about 15 years, but has never been used for generation of meat, while it already is a great source of animal protein. In order to serve as a credible alternative to livestock meat, lab or factory grown meat should be efficiently produced and should mimic meat in all of its physical sensations, such as visual appearance, smell, texture and of course, taste. This is a formidable challenge even though all the technologies to create skeletal muscle and fat tissue have been developed and tested. The efficient culture of meat will primarily depend on culture conditions such as the source of medium and its composition. Protein synthesis by cultured skeletal muscle cells should further be maximized by finding the optimal combination of biochemical and physical conditions for the cells. Many of these variables are known, but their interactions are numerous and need to be mapped. This involves a systematic, if not systems, approach. Given the urgency of the problems that the meat industry is facing, this endeavor is worth undertaking. As an additional benefit, culturing meat may provide opportunities for production of novel and healthier products. Copyright © 2012 Elsevier Ltd. All rights reserved.
SUGIMURA, Satoshi; AKAI, Tomonori; HASHIYADA, Yutaka; AIKAWA, Yoshio; OHTAKE, Masaki; MATSUDA, Hideo; KOBAYASHI, Shuji; KOBAYASHI, Eiji; KONISHI, Kazuyuki; IMAI, Kei
2012-01-01
Abstract To identify embryos individually during in vitro development, we previously developed the well-of-the-well (WOW) dish, which contains 25 microwells. Here we investigated the effect of embryo density (the number of embryos per volume of medium) on in vitro development and gene expression of bovine in vitro-fertilized embryos cultured in WOW dishes. Using both conventional droplet and WOW culture formats, 5, 15, and 25 bovine embryos were cultured in 125 µl medium for 168 h. The blastocysts at Day 7 were analyzed for number of cells and expression of ten genes (CDX2, IFN-tau, PLAC8, NANOG, OCT4, SOX2, AKR1B1, ATP5A1, GLUT1 and IGF2R). In droplet culture, the rates of formation of >4-cell cleavage embryos and blastocysts were significantly lower in embryos cultured at 5 embryos per droplet than in those cultured at 15 or 25 embryos per droplet, but not in WOW culture. In both droplet and WOW culture, developmental kinetics and blastocyst cell numbers did not differ among any groups. IFN-tau expression in embryos cultured at 25 embryos per droplet was significantly higher than in those cultured at 15 embryos per droplet and in artificial insemination (AI)-derived blastocysts. Moreover, IGF2R expression was significantly lower in the 25-embryo group than in the 5-embryo group and in AI-derived blastocysts. In WOW culture, these expressions were not affected by embryo density and were similar to those in AI-derived blastocysts. These results suggest that, as compared with conventional droplet culture, in vitro development and expression of IFN-tau and IGF2R in the microwell system may be insensitive to embryo density. PMID:23154384
NASA Technical Reports Server (NTRS)
Talyansky, Y.; Moyer, E. L.; Oijala, E.; Baer, L. A.; Ronca, A. E.
2016-01-01
During adaptation to the microgravity environment, adult mammals experience stress mediated by the Hypothalamic-Pituitary-Adrenal axis. In our previous studies of pregnant rats exposed to 2-g hypergravity via centrifugation, we reported decreased corticosterone and increased body mass and leptin in adult male, but not female, offspring. In this study, we utilized Unpredictable Variable Prenatal Stress to simulate the stressors of spaceflight by exposing dams to different stressors. Stress response modulation occurs via both positive and negative feedback in the hypothalamus, anterior pituitary gland, and adrenal cortex resulting in the differential release of corticosterone (CORT), a murine analog to human cortisol.
Modelling Influence and Opinion Evolution in Online Collective Behaviour
Gend, Pascal; Rentfrow, Peter J.; Hendrickx, Julien M.; Blondel, Vincent D.
2016-01-01
Opinion evolution and judgment revision are mediated through social influence. Based on a large crowdsourced in vitro experiment (n = 861), it is shown how a consensus model can be used to predict opinion evolution in online collective behaviour. It is the first time the predictive power of a quantitative model of opinion dynamics is tested against a real dataset. Unlike previous research on the topic, the model was validated on data which did not serve to calibrate it. This avoids to favor more complex models over more simple ones and prevents overfitting. The model is parametrized by the influenceability of each individual, a factor representing to what extent individuals incorporate external judgments. The prediction accuracy depends on prior knowledge on the participants’ past behaviour. Several situations reflecting data availability are compared. When the data is scarce, the data from previous participants is used to predict how a new participant will behave. Judgment revision includes unpredictable variations which limit the potential for prediction. A first measure of unpredictability is proposed. The measure is based on a specific control experiment. More than two thirds of the prediction errors are found to occur due to unpredictability of the human judgment revision process rather than to model imperfection. PMID:27336834
Brinkmann, L; Buff, C; Feldker, K; Tupak, S V; Becker, M P I; Herrmann, M J; Straube, T
2017-11-01
Panic disorder (PD) patients are constantly concerned about future panic attacks and exhibit general hypersensitivity to unpredictable threat. We aimed to reveal phasic and sustained brain responses and functional connectivity of the amygdala and the bed nucleus of the stria terminalis (BNST) during threat anticipation in PD. Using functional magnetic resonance imaging (fMRI), we investigated 17 PD patients and 19 healthy controls (HC) during anticipation of temporally unpredictable aversive and neutral sounds. We used a phasic and sustained analysis model to disentangle temporally dissociable brain activations. PD patients compared with HC showed phasic amygdala and sustained BNST responses during anticipation of aversive v. neutral stimuli. Furthermore, increased phasic activation was observed in anterior cingulate cortex (ACC), insula and prefrontal cortex (PFC). Insula and PFC also showed sustained activation. Functional connectivity analyses revealed partly distinct phasic and sustained networks. We demonstrate a role for the BNST during unpredictable threat anticipation in PD and provide first evidence for dissociation between phasic amygdala and sustained BNST activation and their functional connectivity. In line with a hypersensitivity to uncertainty in PD, our results suggest time-dependent involvement of brain regions related to fear and anxiety.
Multiple benefits of alloparental care in a fluctuating environment.
Guindre-Parker, Sarah; Rubenstein, Dustin R
2018-02-01
Although cooperatively breeding vertebrates occur disproportionately in unpredictable environments, the underlying mechanism shaping this biogeographic pattern remains unclear. Cooperative breeding may buffer against harsh conditions (hard life hypothesis), or additionally allow for sustained breeding under benign conditions (temporal variability hypothesis). To distinguish between the hard life and temporal variability hypotheses, we investigated whether the number of alloparents at a nest increased reproductive success or load-lightening in superb starlings ( Lamprotornis superbus ), and whether these two types of benefits varied in harsh and benign years. We found that mothers experienced both types of benefits consistent with the temporal variability hypothesis, as larger contingents of alloparents increased the number of young fledged while simultaneously allowing mothers to reduce their provisioning rates under both harsh and benign rainfall conditions. By contrast, fathers experienced load-lightening only under benign rainfall conditions, suggesting that cooperative breeding may serve to take advantage of unpredictable benign breeding seasons when they do occur. Cooperative breeding in unpredictable environments may thus promote flexibility in offspring care behaviour, which could mitigate variability in the cost of raising young. Our results highlight the importance of considering how offspring care decisions vary among breeding roles and across fluctuating environmental conditions.
Kakouros, Sofoklis; Räsänen, Okko
2016-09-01
Numerous studies have examined the acoustic correlates of sentential stress and its underlying linguistic functionality. However, the mechanism that connects stress cues to the listener's attentional processing has remained unclear. Also, the learnability versus innateness of stress perception has not been widely discussed. In this work, we introduce a novel perspective to the study of sentential stress and put forward the hypothesis that perceived sentence stress in speech is related to the unpredictability of prosodic features, thereby capturing the attention of the listener. As predictability is based on the statistical structure of the speech input, the hypothesis also suggests that stress perception is a result of general statistical learning mechanisms. To study this idea, computational simulations are performed where temporal prosodic trajectories are modeled with an n-gram model. Probabilities of the feature trajectories are subsequently evaluated on a set of novel utterances and compared to human perception of stress. The results show that the low-probability regions of F0 and energy trajectories are strongly correlated with stress perception, giving support to the idea that attention and unpredictability of sensory stimulus are mutually connected. Copyright © 2015 Cognitive Science Society, Inc.
Multiple benefits of alloparental care in a fluctuating environment
2018-01-01
Although cooperatively breeding vertebrates occur disproportionately in unpredictable environments, the underlying mechanism shaping this biogeographic pattern remains unclear. Cooperative breeding may buffer against harsh conditions (hard life hypothesis), or additionally allow for sustained breeding under benign conditions (temporal variability hypothesis). To distinguish between the hard life and temporal variability hypotheses, we investigated whether the number of alloparents at a nest increased reproductive success or load-lightening in superb starlings (Lamprotornis superbus), and whether these two types of benefits varied in harsh and benign years. We found that mothers experienced both types of benefits consistent with the temporal variability hypothesis, as larger contingents of alloparents increased the number of young fledged while simultaneously allowing mothers to reduce their provisioning rates under both harsh and benign rainfall conditions. By contrast, fathers experienced load-lightening only under benign rainfall conditions, suggesting that cooperative breeding may serve to take advantage of unpredictable benign breeding seasons when they do occur. Cooperative breeding in unpredictable environments may thus promote flexibility in offspring care behaviour, which could mitigate variability in the cost of raising young. Our results highlight the importance of considering how offspring care decisions vary among breeding roles and across fluctuating environmental conditions. PMID:29515910
Predictions interact with missing sensory evidence in semantic processing areas.
Scharinger, Mathias; Bendixen, Alexandra; Herrmann, Björn; Henry, Molly J; Mildner, Toralf; Obleser, Jonas
2016-02-01
Human brain function draws on predictive mechanisms that exploit higher-level context during lower-level perception. These mechanisms are particularly relevant for situations in which sensory information is compromised or incomplete, as for example in natural speech where speech segments may be omitted due to sluggish articulation. Here, we investigate which brain areas support the processing of incomplete words that were predictable from semantic context, compared with incomplete words that were unpredictable. During functional magnetic resonance imaging (fMRI), participants heard sentences that orthogonally varied in predictability (semantically predictable vs. unpredictable) and completeness (complete vs. incomplete, i.e. missing their final consonant cluster). The effects of predictability and completeness interacted in heteromodal semantic processing areas, including left angular gyrus and left precuneus, where activity did not differ between complete and incomplete words when they were predictable. The same regions showed stronger activity for incomplete than for complete words when they were unpredictable. The interaction pattern suggests that for highly predictable words, the speech signal does not need to be complete for neural processing in semantic processing areas. Hum Brain Mapp 37:704-716, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.
Garrido, Marta I; Rowe, Elise G; Halász, Veronika; Mattingley, Jason B
2018-05-01
Predictive coding posits that the human brain continually monitors the environment for regularities and detects inconsistencies. It is unclear, however, what effect attention has on expectation processes, as there have been relatively few studies and the results of these have yielded contradictory findings. Here, we employed Bayesian model comparison to adjudicate between 2 alternative computational models. The "Opposition" model states that attention boosts neural responses equally to predicted and unpredicted stimuli, whereas the "Interaction" model assumes that attentional boosting of neural signals depends on the level of predictability. We designed a novel, audiospatial attention task that orthogonally manipulated attention and prediction by playing oddball sequences in either the attended or unattended ear. We observed sensory prediction error responses, with electroencephalography, across all attentional manipulations. Crucially, posterior probability maps revealed that, overall, the Opposition model better explained scalp and source data, suggesting that attention boosts responses to predicted and unpredicted stimuli equally. Furthermore, Dynamic Causal Modeling showed that these Opposition effects were expressed in plastic changes within the mismatch negativity network. Our findings provide empirical evidence for a computational model of the opposing interplay of attention and expectation in the brain.
Transparent, biocompatible nanostructured surfaces for cancer cell capture and culture
Cheng, Boran; He, Zhaobo; Zhao, Libo; Fang, Yuan; Chen, Yuanyuan; He, Rongxiang; Chen, Fangfang; Song, Haibin; Deng, Yuliang; Zhao, Xingzhong; Xiong, Bin
2014-01-01
Circulating tumor cells (CTCs) in the blood which have detached from both the primary tumor and any metastases may be considered as a “liquid biopsy” and are expected to replace tumor biopsies in the monitoring of treatment response and determining patient prognosis. Here, we introduce a facile and efficient CTC detection material made of hydroxyapatite/chitosan (HA/CTS), which is beneficial because of its transparency and excellent biological compatibility. Atomic force microscopy images show that the roughness of the HA/CTS nanofilm (HA/CTSNF) substrates can be controlled by changing the HA:CTS ratio. Enhanced local topographic interactions between nano-components on cancer cell membranes, and the antibody coated nanostructured substrate lead to improved CTC capture and separation. This remarkable nanostructured substrate has the potential for CTC culture in situ and merits further analysis. CTCs captured from artificial blood samples were observed in culture on HA/CTSNF substrates over a period of 14 days by using conventional staining methods (hematoxylin eosin and Wright’s stain). We conclude that these substrates are multifunctional materials capable of isolating and culturing CTCs for subsequent studies. PMID:24904216
Habib, I; Sampers, I; Uyttendaele, M; Berkvens, D; De Zutter, L
2008-02-01
In this work, we present an intra-laboratory study in order to estimate repeatability (r), reproducibility (R), and measurement uncertainty (U) associated with three media for Campylobacter enumeration, named, modified charcoal cefoperazone deoxycholate agar (mCCDA); Karmali agar; and CampyFood ID agar (CFA) a medium by Biomérieux SA. The study was performed at three levels: (1) pure bacterial cultures, using three Campylobacter strains; (2) artificially contaminated samples from three chicken meat matrixes (total n=30), whereby samples were spiked using two contamination levels; ca. 10(3)cfuCampylobacter/g, and ca. 10(4)cfuCampylobacter/g; and (3) pilot testing in naturally contaminated chicken meat samples (n=20). Results from pure culture experiment revealed that enumeration of Campylobacter colonies on Karmali and CFA media was more convenient in comparison with mCCDA using spread and spiral plating techniques. Based on artificially contaminated samples testing, values of repeatability (r) were comparable between the three media, and estimated as 0.15log(10)cfu/g for mCCDA, 0.14log(10)cfu/g for Karmali, and 0.18log(10)cfu/g for CFA. As well, reproducibility performance of the three plating media was comparable. General R values which can be used when testing chicken meat samples are; 0.28log(10), 0.32log(10), and 0.25log(10) for plating on mCCDA, Karmali agar, and CFA, respectively. Measurement uncertainty associated with mCCDA, Karmali agar, and CFA using spread plating, for combination of all meat matrixes, were +/-0.24log(10)cfu/g, +/-0.28log(10)cfu/g, and +/-0.22log(10)cfu/g, respectively. Higher uncertainty was associated with Karmali agar for Campylobacter enumeration in artificially inoculated minced meat (+/-0.48log(10)cfu/g). The general performance of CFA medium was comparable with mCCDA performance at the level of artificially contaminated samples. However, when tested at naturally contaminated samples, non-Campylobacter colonies gave similar deep red colour as that given by the typical Campylobacter growth on CFA. Such colonies were not easily distinguishable by naked eye. In general, the overall reproducibility, repeatability, and measurement uncertainty estimated by our study indicate that there are no major problems with the precision of the International Organization for Standardization (ISO) 10272-2:2006 protocol for Campylobacter enumeration using mCCDA medium.
Global facial beauty: approaching a unified aesthetic ideal.
Sands, Noah B; Adamson, Peter A
2014-04-01
Recognition of facial beauty is both inborn and learned through social discourses and exposures. Demographic shifts across the globe, in addition to cross-cultural interactions that typify 21st century globalization in virtually all industries, comprise major active evolutionary forces that reshape our individual notions of facial beauty. This article highlights the changing perceptions of beauty, while defining and distinguishing natural beauty and artificial beauty. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
Waese, Elaine Y L; Stanford, William L
2011-01-01
Cartilage defects have limited capacity for repair and are often replaced by fibrocartilage with inferior mechanical properties. To overcome the limitations of artificial joint replacement, high-throughput screens (HTS) could be developed to identify molecules that stimulate differentiation and/or proliferation of articular cartilage for drug therapy or tissue engineering. Currently embryonic stem cells (ESCs) can differentiate into articular cartilage by forming aggregates (embryoid body (EB), pellet, micromass), which are difficult to image. We present a novel, single-step method of generating murine ESC-derived chondrocytes in monolayer cultures under chemically defined conditions. Mesoderm induction was achieved in cultures supplemented with BMP4, activin A, or Wnt3a. Prolonged culture with sustained activin A, TGFβ3, or BMP4 supplementation led to robust chondrogenic induction. A short pulse of activin A or BMP4 also induced chondrogenesis efficiently while Wnt3a acted as a later inducer. Long-term supplementation with activin A or with activin A followed by TGFβ3 promoted articular cartilage formation. Thus, we devised a serum-free (SF) culture system to generate ESC-derived chondrocytes without the establishment of 3D cultures or the aid of cell sorting. Cultures were governed by the same signaling pathways as 3D ESC differentiation systems and limb bud mesenchyme or articular cartilage explant cultures. Copyright © 2010 Elsevier B.V. All rights reserved.
Social network- and community-level influences on contraceptive use: evidence from rural Poland
Colleran, Heidi; Mace, Ruth
2015-01-01
The diffusion of ‘modern’ contraceptives—as a proxy for the spread of low-fertility norms—has long interested researchers wishing to understand global fertility decline. A fundamental question is how local cultural norms and other people's behaviour influence the probability of contraceptive use, independent of women's socioeconomic and life-history characteristics. However, few studies have combined data at individual, social network and community levels to simultaneously capture multiple levels of influence. Fewer still have tested if the same predictors matter for different contraceptive types. Here, we use new data from 22 high-fertility communities in Poland to compare predictors of the use of (i) any contraceptives—a proxy for the decision to control fertility—with those of (ii) ‘artificial’ contraceptives—a subset of more culturally taboo methods. We find that the contraceptive behaviour of friends and family is more influential than are women's own characteristics and that community level characteristics additionally influence contraceptive use. Highly educated neighbours accelerate women's contraceptive use overall, but not their artificial method use. Highly religious neighbours slow women's artificial method use, but not their contraceptive use overall. Our results highlight different dimensions of sociocultural influence on contraceptive diffusion and suggest that these may be more influential than are individual characteristics. A comparative multilevel framework is needed to understand these dynamics. PMID:25904669
Resource Management in Constrained Dynamic Situations
NASA Astrophysics Data System (ADS)
Seok, Jinwoo
Resource management is considered in this dissertation for systems with limited resources, possibly combined with other system constraints, in unpredictably dynamic environments. Resources may represent fuel, power, capabilities, energy, and so on. Resource management is important for many practical systems; usually, resources are limited, and their use must be optimized. Furthermore, systems are often constrained, and constraints must be satisfied for safe operation. Simplistic resource management can result in poor use of resources and failure of the system. Furthermore, many real-world situations involve dynamic environments. Many traditional problems are formulated based on the assumptions of given probabilities or perfect knowledge of future events. However, in many cases, the future is completely unknown, and information on or probabilities about future events are not available. In other words, we operate in unpredictably dynamic situations. Thus, a method is needed to handle dynamic situations without knowledge of the future, but few formal methods have been developed to address them. Thus, the goal is to design resource management methods for constrained systems, with limited resources, in unpredictably dynamic environments. To this end, resource management is organized hierarchically into two levels: 1) planning, and 2) control. In the planning level, the set of tasks to be performed is scheduled based on limited resources to maximize resource usage in unpredictably dynamic environments. In the control level, the system controller is designed to follow the schedule by considering all the system constraints for safe and efficient operation. Consequently, this dissertation is mainly divided into two parts: 1) planning level design, based on finite state machines, and 2) control level methods, based on model predictive control. We define a recomposable restricted finite state machine to handle limited resource situations and unpredictably dynamic environments for the planning level. To obtain a policy, dynamic programing is applied, and to obtain a solution, limited breadth-first search is applied to the recomposable restricted finite state machine. A multi-function phased array radar resource management problem and an unmanned aerial vehicle patrolling problem are treated using recomposable restricted finite state machines. Then, we use model predictive control for the control level, because it allows constraint handling and setpoint tracking for the schedule. An aircraft power system management problem is treated that aims to develop an integrated control system for an aircraft gas turbine engine and electrical power system using rate-based model predictive control. Our results indicate that at the planning level, limited breadth-first search for recomposable restricted finite state machines generates good scheduling solutions in limited resource situations and unpredictably dynamic environments. The importance of cooperation in the planning level is also verified. At the control level, a rate-based model predictive controller allows good schedule tracking and safe operations. The importance of considering the system constraints and interactions between the subsystems is indicated. For the best resource management in constrained dynamic situations, the planning level and the control level need to be considered together.
Swathi, S; Ramesh, A; Nagapoornima, M; Fernandes, Lavina M; Jisina, C; Rao, P N Suman; Swarnarekha, A
2014-01-01
The aim of this study was to generate a substantive theory explaining how the staff in a resource-limited neonatal intensive care unit (NICU) of a developing nation manage to ensure adherence to behavioral modification components of a noise reduction protocol (NsRP) during nonemergency situations. The study was conducted after implementation of an NsRP in a level III NICU of south India. The normal routine of the NICU is highly dynamic because of various categories of staff conducting clinical rounds followed by care-giving activities. This is unpredictably interspersed with very noisy emergency management of neonates who suddenly fall sick. In-depth interviews were conducted with 36 staff members of the NICU (20 staff nurses, six nursing aides, and 10 physicians). Group discussions were conducted with 20 staff nurses and six nursing aides. Data analysis was done in line with the reformulated grounded theory approach, which was based on inductive examination of textual information. The results of the analysis showed that the main concern was to ensure adherence to behavioral modification components of the NsRP. This was addressed by using strategies to "sustain a culture of silence in NICU during nonemergency situations" (core category). The main strategies employed were building awareness momentum, causing awareness percolation, developing a sense of ownership, expansion of caring practices, evolution of adherence, and displaying performance indicators. The "culture of silence" reconditions the existing staff and conditions new staff members joining the NICU. During emergency situations, a "noisy culture" prevailed because of pragmatic neglect of behavioral modification when life support overrode all other concerns. In addition to this, the process of operant conditioning should be formally conducted once every 18 months. The results of this study may be adapted to create similar strategies and establish context specific NsRPs in NICUs with resource constraints.
Stillaert, Filip; Depypere, Bernard; Doornaert, Maarten; Creytens, David; De Clercq, Heidi; Cornelissen, Ria; Monstrey, Stan; Blondeel, Phillip
2016-07-01
Fat grafting has become a widespread technique for different reconstructive and esthetic purposes. However, the disadvantage of fat grafting is the unpredictable resorption rate that often necessitates repetitive procedures, which in turn may have an impact on the morbidity. During the immediate, post-graft, ischemic period, cells survive due to the process of plasmatic imbibition. This biological phenomenon precedes the ingrowth of neo-capillaries that eventually nourish the graft and help establish a long-term homeostatic equilibrium. Both partners, the graft and the recipient bed, contribute to the revascularization process. Hypothetically, enrichment of the recipient site with autologous plasma could have a beneficial role to enhance fat graft survival. We investigated whether plasma supported the viability of the lipoaspirate (LA) material. Plasma was isolated from blood samples collected from eight patients during the elective lipofilling procedures. An in vitro study assessed the viability of LA cells using plasma as a culture medium compared to the traditional culture media. In vitro analysis confirmed sustained viability of LA cells compared to the standard media and control media during 7 consecutive days. The behavior of the fat grafts in plasma showed similarities with those incubated in the traditional culture media. In future, these findings could be translated to a clinical setting. Plasma is the only autologous substrate available in large quantities in the human body. The addition of the supporting agents, such as plasma, could contribute to a better graft survival with more stable clinical outcomes in the long term. The rationale behind the technique is based on the phenomenon of plasmatic imbibition and the reasoning that the extracellular matrix plays a pivotal role in cellular survival. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.
Chan, Keung-Sum; Twinn, Sheila
2007-01-01
The aim of this study was to identify the major stressors affecting Chinese adults whose partner had been admitted to an intensive care unit and to understand the major coping strategies employed to manage such stressors. Recently a greater number of patients of higher acuity have been admitted to intensive care units and survive lengthy illnesses of an unpredictable course. Such critical illnesses have been identified as a major life event to family members of these patients. Little is known, however, about the stressors and coping mechanisms of Chinese adults whose critically ill partner is admitted to an intensive care unit. An exploratory qualitative design was selected to achieve the aims of the study. A purposive sample of 10 Chinese adults with a partner in an intensive care unit of a regional general hospital in Hong Kong participated in tape-recorded semi-structured interviews. Content analysis was employed to analyse the translated interviews. Categories of stressors included uncertainty, difficulties in communication, changes in roles and responsibilities, difficulties in decision making, financial strain as well as changes in relationships. Analysis identified a range of coping strategies which included seeking information, seeking support, reliance on cultural beliefs and practices, turning to religious beliefs, maintaining hope and acceptance of illness. The findings demonstrate the importance of cultural beliefs and practices in determining the coping mechanisms employed to manage the stressors identified by this sample of Chinese adults. Such findings indicate the use of both internal and external coping strategies in order to maintain equilibrium in the family. Implications for nursing practice highlight the significance of seeking information throughout the critical period and also culturally appropriate support from healthcare professionals.
Morrow, Gill; Burford, Bryan; Carter, Madeline; Illing, Jan
2014-03-06
To explore the effects of the UK Working Time Regulations (WTR) on trainee doctors' experience of fatigue. Qualitative study involving focus groups and telephone interviews, conducted in Spring 2012 with doctors purposively selected from Foundation and specialty training. Final compliance with a 48 h/week limit had been required for trainee doctors since August 2009. Framework analysis of data. 9 deaneries in all four UK nations; secondary care. 82 doctors: 53 Foundation trainees and 29 specialty trainees. 36 participants were male and 46 female. Specialty trainees were from a wide range of medical and surgical specialties, and psychiatry. Implementation of the WTR, while acknowledged as an improvement to the earlier situation of prolonged excessive hours, has not wholly overcome experience of long working hours and fatigue. Fatigue did not only arise from the hours that were scheduled, but also from an unpredictable mixture of shifts, work intensity (which often resulted in educational tasks being taken home) and inadequate rest. Fatigue was also caused by trainees working beyond their scheduled hours, for reasons such as task completion, accessing additional educational opportunities beyond scheduled hours and staffing shortages. There were also organisational, professional and cultural drivers, such as a sense of responsibility to patients and colleagues and the expectations of seniors. Fatigue was perceived to affect efficiency of skills and judgement, mood and learning capacity. Long-term risks of continued stress and fatigue, for doctors and for the effective delivery of a healthcare service, should not be ignored. Current monitoring processes do not reflect doctors' true working patterns. The effectiveness of the WTR cannot be considered in isolation from the culture and context of the workplace. On-going attention needs to be paid to broader cultural issues, including the relationship between trainees and seniors.
Li, Pei; Gan, Yibo; Wang, Haoming; Xu, Yuan; Song, Lei; Wang, Liyuan; Ouyang, Bin; Zhou, Qiang
2017-11-01
Various research models have been developed to study the biology of disc cells. Recently, the adult disc nucleus pulposus (NP) has been well studied. However, the immature NP is underinvestigated due to a lack of a suitable model. This study aimed to establish an organ culture of immature porcine disc by optimizing culture conditions and using a self-developed substance exchanger-based bioreactor. Immature porcine discs were first cultured in the bioreactor for 7 days at various levels of glucose (low, medium, high), osmolarity (hypo-, iso-, hyper-) and serum (5, 10, 20%) to determine the respective optimal level. The porcine discs were then cultured under the optimized conditions in the novel bioreactor, and were compared with fresh discs at day 14. For high-glucose, iso-osmolarity, or 10% serum, cell viability, the gene expression profile (for anabolic genes and catabolic genes), and glycosaminoglycan (GAG) and hydroxyproline (HYP) contents were more favorable than for other levels of glucose, osmolarity, and serum. When the immature discs were cultured under the optimized conditions using the novel bioreactor for 14 days, the viability of the immature NP was maintained based on histology, cell viability, GAG and HYP contents, and matrix molecule expression. In conclusion, the viability of the immature NP in organ culture could be maintained under the optimized culture conditions (high-glucose, iso-osmolarity, and 10% serum) in the substance exchanger-based bioreactor. © 2017 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.
Berginc, Katja; Zakelj, Simon; Levstik, Lea; Ursic, Darko; Kristl, Albin
2007-05-01
Membrane transport characteristics of a paracellular permeability marker fluorescein were evaluated using artificial membrane, Caco-2 cell monolayers and rat jejunum, all mounted in side-by-side diffusion cells. Modified Ringer buffers with varied pH values were applied as incubation salines on both sides of artificial membrane, cell culture monolayers or rat jejunum. Passive transport according to pH partition theory was determined using all three permeability models. In addition to that, active transport of fluorescein in the M-S (mucosal-to-serosal) direction through rat jejunum was observed. The highest M-S P(app) values regarding the active transport through the rat jejunum were observed in incubation saline with pH 6.5. Fluorescein transport through the rat jejunum was inhibited by DIDS (4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid) and alpha-CHC (alpha-cyano-4-hydroxycinnamic acid). Thus, we assume that two pH-dependent influx transporters could be involved in the fluorescein membrane transport through the intestinal (jejunal) epithelium. One is very likely an MCT (monocarboxylic acid cotransporter) isoform, inhibited by specific MCT inhibitor alpha-CHC, while the involvement of the second one with overlapping substrate/inhibitor specificities (most probably a member of the organic anion-transporting polypeptide family, inhibited at least partially by DIDS) could not be excluded.
Kamenickova, Alzbeta; Pecova, Michaela; Bachleda, Petr; Dvorak, Zdenek
2013-12-01
Food constituents may cause a phenomenon of food-drug interactions. In the current study, we examined the effects of artificial sweeteners (aspartame, acesulfame, cyclamate, saccharin) on the aryl hydrocarbon receptor (AhR) and glucocorticoid receptor (GR)-dependent expression of CYP1A1 in human hepatocytes, hepatic HepG2 and intestinal LS174T cancer cell lines. Sweeteners were tested in concentrations up to those occurring in non-alcoholic beverages. Basal and ligand-inducible AhR- and GR-dependent reporter gene activation in stably transfected HepG2 and HeLa cells, respectively, were not affected by either of the sweeteners tested after 24h of incubation. The expression of CYP1A1 mRNA and protein in primary cultures of human hepatocytes and in LS174T and HepG2 cells was not induced by any of the tested sweeteners. Overall, aspartame, acesulfame, saccharin and cyclamate had no effects on CYP1A1 expression and transcriptional activities of AhR and GR. These data imply the safety of artificial sweeteners in terms of interference with AhR, GR and CYP1A1. Copyright © 2013 Elsevier Ltd. All rights reserved.
Lefrancq, B; Lateur, M
2006-01-01
In 1988, the Department of Biological Control and Plant Genetic Resources at the Walloon Agricultural Research Centre started an apple-breeding programme using local genetic resources and modern varieties. Our objective is to create high quality commercial cultivars with durable resistance to scab (Venturia inaequalis), powdery mildew (Podosphaera leucotricha) and canker (Nectria galligena). The breeding strategy is based on crossing old apple cultivars and landraces selected as parents for low disease susceptibility and possessing other desirable horticultural characteristics. The programme aims to develop an early and efficient selection methodology adapted to partial disease resistance. One of the objectives is to define the optimal screening limit for discarding individuals after artificial scab inoculation tests. Working with large populations of seedlings entails spacing the seedling scab tests throughout the year. In order to work during winter, seedlings were grown in controlled cabinet conditions and in a glasshouse with supplementary lighting. To assess the bias introduced by these conditions, two trials were conducted: the first one to compare the influence of both environments on the results of scab inoculation tests, and the second one to assess the influence of the duration of supplementary lighting. The results enabled us to evaluate the limits of artificial cultural systems.
NASA Astrophysics Data System (ADS)
Dhawan, Udesh; Wang, Ssu-Meng; Chu, Ying Hao; Huang, Guewha S.; Lin, Yan Ren; Hung, Yao Ching; Chen, Wen Liang
2016-08-01
Nanotopography modulates cell characteristics and cell behavior. Nanotopological cues can be exploited to investigate the in-vivo modulation of cell characteristics by the cellular microenvironment. However, the studies explaining the modulation of tumor cell characteristics and identifying the transition step in cancer progressiveness are scarce. Here, we engineered nanochips comprising of Tantalum oxide nanodot arrays of 10, 50, 100 and 200 nm as artificial microenvironments to study the modulation of cancer cell behavior. Clinical samples of different types of Ovarian cancer at different stages were obtained, primary cultures were established and then seeded on different nanochips. Immunofluorescence (IF) was performed to compare the morphologies and cell characteristics. Indices corresponding to cell characteristics were defined. A statistical comparison of the cell characteristics in response to the nanochips was performed. The cells displayed differential growth parameters. Morphology, Viability, focal adhesions, microfilament bundles and cell area were modulated by the nanochips which can be used as a measure to study the cancer progressiveness. The ease of fabrication of nanochips ensures mass-production. The ability of the nanochips to act as artificial microenvironments and modulate cell behavior may lead to further prospects in the markerless monitoring of the progressiveness and ultimately, improving the prognosis of Ovarian cancer.
Hogan, Matthew; Mohamed, Mohamed; Tao, Ze-Wei; Gutierrez, Laura; Birla, Ravi
2015-02-01
Only 3000 heart transplants are performed in the USA every year, leaving some 30 000-70 000 Americans without proper care. Current treatment modalities for heart failure have saved many lives yet still do not correct the underlying problems of congestive heart failure. Tissue engineering represents a potential field of study wherein a combination of cells, scaffolds, and/or bioreactors can be utilized to create constructs to mimic, replace, and/or repair defective tissue. The focus of this study was to generate a bioartificial heart (BAH) model using artificial heart muscle (AHM), composed of fibrin gel and neonatal rat cardiac myocytes, and a decellularized scaffold, formed by subjecting an adult rat heart to a series of decellularization solutions. By suturing the AHM around the outside of the decellularized heart and culturing while suspended in media, we were able to retain functional cardiac cells on the scaffold as evinced by visible contractility. Observed contractility rate was correlated with biopotential measurements to confirm essential functionality of cardiac constructs. Cross-sections of the BAH show successful decellularization of the scaffold and contiguous cell-rich AHM around the perimeter of the heart. Copyright © 2014 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.
Jiang, Jia; Ai, Chengchong; Zhan, Zufeng; Zhang, Peng; Wan, Fang; Chen, Jun; Hao, Wei; Wang, Yaxian; Yao, Jinrong; Shao, Zhengzhong; Chen, Tianwu; Zhou, Liang; Chen, Shiyi
2016-04-01
Artificial ligaments utilized in reconstruction of anterior cruciate ligament (ACL) are usually made of polyethylene terepthalate (PET) because of its good mechanical properties in vivo. However, it was found that the deficiencies in hydrophilicity and biocompatibility of PET hindered the process of ligamentization. Therefore, surface modification of the PET is deemed as a solution in resolving such problem. Silk fibroin (SF), which is characterized by good biocompatibility and low immunogenicity in clinical applications, was utilized to prepare a coating on the PET ligament (PET+SF) in this work. At first, decrease of hydrophobicity and appearance of amino groups were found on the surface of artificial PET ligament after coating with SF. Second, mouse fibroblasts were cultured on the two different kinds of ligament in order to clarify the possible effect of SF coating. It was proved that mouse fibroblasts display better adhesion and proliferation on PET+SF than PET ligament according to the results of several technical methods including SEM observation, cell adhesive force and spread area test, and mRNA analysis. Meanwhile, methylthiazolyldiphenyl-tetrazolium bromide and DNA content tests showed that biocompatibility of PET+SF is better than PET ligament. In addition, collagen deposition tests also indicated that the quantity of collagen in PET+SF is higher than PET ligament. Based on these results, it can be concluded that SF coating is suggested to be an effective approach to modify the surface of PET ligament and enhance the "ligamentization" process in vivo accordingly. Copyright © 2015 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.
The research on regional conservation planning of urban historical and cultural areas based on GIS
NASA Astrophysics Data System (ADS)
Li, Shangli; Xu, Jian; Li, Qian
2017-06-01
With the rapid economic development and the growth of population happening in the urban historical and cultural areas, heritage and historical buildings along with their natural and artificial surrounding environments are suffering constructive destruction. Due to the lack of precise partition of protection region and construction control region in the local cultural relics protection law, traditional regional conservation planning cannot engaged with the urban controllability detailed planning very well. According to the several protection regulations about heritage and historical buildings from latest laws, we choose Baxian Temple area to study on the improvments of traditional regional conservation planning. The technical methods of this study mainly rely on GIS, which can complete the fundamental work of each stage. With the analytic hierarchy process(AHP), the comprehensive architectural value assessments can be calculated according to the investigation results. Based on the calculation results and visual corridor analysis, the precise range of protection region and construction control region can be decided and the specific protection measures can be formulated.